Important note - before I begin, it needs to be acknowledged that a post like this should really be ten miles long and riddled with links to the many studies, news articles and anecdotes that corroborate what's said here. However, this isn't possible for several reasons. Therefore, this post will be a summary of a summary of a summary of what can really be written on this topic, feel free to add whatever important points you feel are missing in the comment section. I also will not be adding any links. All the evidence has been covered extensively by others and can be easily found in the various RP, MGTOW and MRA subs, blogs and YouTube channels.
The olden days
Go back to before the industrial revolution and life was brutal and short. Poverty, starvation and serfdom were a way of life for most people. No one had rights, everyone had responsibility. Responsibility to your parents, your spouse, your children, your community and God. War and disease were real, ever present dangers that could strike at any moment.
In this context, the man was in charge of his family. He had to be, his wife needed him to be, his children needed him to be and his elderly parents needed him to be in charge of the household. As the strongest member of the family whose hormones don't yo-yo, it made most sense for him to be the undisputed leader. This was so out of necessity of life, not because men are tyrants nor because women are pushovers. There simply wasn't any other way to survive and raise the future generation.
Massive, unprecedented changes swept over the world with the industrial revolution. The brute force of male muscle was being replaced by machines in factories. Sure, men still needed muscle to operate many of those old machines, but that was a step away from the back-breaking labor that preceded the invention of industry. Thus, men were slightly less needed in their traditional roles. The first seeds of feminism and rights for women soon followed. (Many other changes came to the world as a result, we will only focus on what's pertinent to this very specific discussion).
As society developed, the need for the husbands protection diminished due to communities being better protected against marauding bandits and the like. The need for the husbands provision was diminished because women can also operate many of the machines which required less and less brute muscle power. The idea of equality for women became more and more of a debate in its many manifestations. This was never a viable thought before the industrial revolution because there was no way a woman could survive in the world without a man in her life.
The birth control pill
The one thing that drastically changed the debate and was perhaps the main contributing factor to ushering in second wave feminism and the sexual revolution of the 60"s was the birth control pill. With the pill, a woman could have sex without the risk of pregnancy! This is when marriage took the bullet of death, the institution has been bleeding out ever since.
In the past, if a woman got pregnant out of wedlock, she was royally screwed. In the distant past, she had little chance of survival in the harsh elements even if she wasn't pregnant, nursing or raising a child. Since the industrial revolution, she could work in a factory, but that wasn't possible while pregnant and nursing etc. Getting pregnant had serious life altering consequences and that's why women were extremely selective about whom they had sex with. For this reason, women needed marriage as a form of security before you were allowed to even think about sex.
All this changed with the pill. Women were now free to have consequence free sex, and that's exactly what they did! Women "threw off" the old shackles of "sexual oppression" and were now "liberated". Men went along with it because what man wants to turn down free sex? Please see - [Women are the gatekeepers of sex](https://www.reddit.com/r/RedPillWomen/comments/8dgnhj/back_to_the_basics_women_are_the_gatekeepers_of/)
The Red Pill
As you can see, feminism evolved as a natural result of modernization. Various mini evolution processes within feminism can be traced to specific developments in modern invention that raised the standard of life and thus diminished the absolute need for a husband to a need that was less absolute and then less of a need. To discuss each specific step along the way is way too long and has been covered extensively by others. The point here is to observe that these changes coincide with ever shifting changes in the standard of living and the family dynamic.
All this led to greater and greater freedoms for women and unleashed female sexuality in a way the world has never seen. Never before was female sexuality unrestrained like it is today. At first, remnants of old values still existed and so it wasn't that bad for men. However, as time progressed and society continued to shift, the individual man became less and less needed to the individual woman while the collective man (via the government) became more and more the replacement husband. Women began demanding things from the government and the government husband began to fulfill those demands because women are the majority of the voters. Divorce laws, child custody laws, laws pertaining to domestic and sexual violence all began shifting in a manner that favors women and mistreats men.
Additionally, female sexuality is [hypergamous](https://www.reddit.com/r/RedPillWomen/comments/8fujkz/back_to_the_basics_hypergamy/) This resulted in more and more men being deemed undesirable and excluded from the sexual market place. Most of these men aren't objectively undesirable, they would have made wonderful husbands in the past. They have become undesirable due to unrestrained hypergamy.
Furthermore, men began to notice how much the game was rigged against them. Free love is only free if you're on top of the attractiveness scale, otherwise you have to pay. Even if you do take on a wife and happily pay for her, she can leave you at any time for any reason and take away most of what you worked for through alimony and child support. She can claim domestic abuse and she'll be believed, she can claim rape and she'll be believed. As a man, your life can be over if any of these things happen to you, how much more so is your life over if all of them happen.
A bitter, bitter pill
Thus, The Red Pill was born. Men began forming online communities and trading notes with each other. Some men were burned through divorce and/or false allegations. Some were burned through harsher trials and longer prison sentences for the same crimes. Some were excluded from the sexual market place. Some weren't burned at all, they simply watched others get burned from touching the hot stove and decided not to do the same.
The logical conclusion is to walk away from all women until the pendulum swings back to a normal, fair and sustainable place. However, this is not easy at all! Men have a tremendous sexual drive that is insanely massive and ever present. Forgoing women and sex altogether is nearly impossible for most men. So what's a man to do? How does one engage with the positive sides of women without being burned by the ever increasing negative side? This inner struggle is why taking TRP is so bitter for men. This is why most men don't take TRP, TRP is forced down the throat of men by women in most cases. Women instinctively know this, that's why the first question often is - who hurt you?
The answer to this question (how to engage without being burned) is a topic of great debate in TRP communities. The first thing many men try is the MRA route. This seems the most sensible way to restore equilibrium. However, the MRA has been around for quite some time with no real results. This is because feminism is the natural outgrowth of societal changes that released biological tendencies (as explained above). Therefore, while every RP man believes in the MRA, most aren't willing to engage in a futile battle. Instead, some will enjoy the decline through learning game and pumping and dumping. Some will incorporate RP ideas within their marriages. Some will go MGTOW. There's no objectively true answer as all the options are disgustingly bitter pills to swallow.
Feminism was a natural result of hidden/squashed biological traits of female sexuality being released due to modernization. TRP is male self preservation being unleashed as a direct progression from feminism. TRP is contrary to the core of male sexual desire and is therefore an extremely bitter pill to swallow, albeit extremely necessary.