“Stay a virgin til marriage” but they’re most likely not virgins themselves.

This advice is most likely based in the idea and the ideal when BOTH men and women married in their very early 20s as was formerly the case as opposed to many folks who now marry in their mid to late 20s (and for some their early 30s).

Preserving virginity is practical advice and not so far-fetched...assuming BOTH parties are very young, in sync, and on track with genuine interest and attraction for each other, great compatibility, shared life goals, and shared life-interests. That - and assuming BOTH parties are SERIOUS about marriage, family, and lifetime commitment.

"...if your person of romantic interest is really interested in you for the long term, they will not care about your number."

I submit most men have concern about a woman's number of partners and overall sexual history. The issue is when N-Count is high or incredibly high as is the case with some women. Example - there was a woman on one of the relationship (SubReddit) forums who spent her undergrad, graduate years, and PhD study years accumulating an N-Count of over 200 partners and experimenting with recreational drugs - seven to eight years in all. She asked a bunch of internet strangers if she should reveal this information to potential suitors or a prospective husband.

This woman's base inquiry and anonymity the internet offers reflects the shame and embarrassment of her behavior. If she were proud of her sexual past, she would have NO PROBLEM revealing the truth to any potential suitor - Period.

There's an issue when this and similar women still consider themselves as a catch. The example for this woman is extreme, but there are women who have a 28-40 plus N-Count who outright lie and worry that men will discover their past.

All this - which leads to your continued point - "It’s all about how you carry yourself and your actions as an individual."

There's truth in this statement as women with very low N-Count do much better than promiscuous women in follow-on relationships assuming all the positive characteristics and traits of femininity, loyalty, respect for their partner, personal integrity, and demonstrated wife and exceptional mother potential is present. Promiscuous and emotionally damaged women can "pretend" and fake these traits in the short-term but have trouble sustaining these same traits over the long-term. I've seen this play out enough times. It's virtually impossible to hide one's true, core personality - that goes for men as well.

On this - "many people seem to prefer a partner with experience (not TOO much generally) and someone who knows what they want."

Sexual experience is unnecessary, but genuine attraction, enthusiasm, and open willingness to please one's partner are basic must-haves. Is seems as if people use the "preference for someone with sexual experience" as justification to engage sexual activity or to seem hip with current dating trends. When I say this in discussion with others men are usually in agreement, but most women express a different sentiment.

A man or woman with sexual experience does not mean the next person will receive the benefit of that "experience." There are numerous relationship and marriage forums filled with folks who were previously promiscuous but have little to no sexual interest in their mate/spouse. This issue mostly affects men. Some of these men are in fact very aware of a woman's history yet confused on the overwhelming lack of post-marriage sexual activity because the woman basically pulled a fast one/Bait and Switch scam...great, crazy, and amazing sex to "lock in" marriage, but virtually no sex post-marriage.

Good points overall, but simply adding more perspective...