I feel like I'm reading a stereotype and what's missing is more face-to-face reporting type research. I'm sure your writing applies to someone.

I know quite a few women 30s and up who are flexible easygoing partners, it's true that they're not going into relationships that easily, and it's because the grind and merry go round of dating and not having it be something more, is tiring emotionally. It's not unwillingness to compromise, if someone is all in with them, most will make it there, it's an unwillingness to be with someone who doesn't show enough interest and near equal desire to compromise and contribute. They don't have to know all the same relationship research or whatever, they do need to be willing to listen to what's needed and care about it because it's needed and to be able to articulate their own needs.

There's no point in doing a ton of work with someone who really wants someone else but goes with you because you're there. These women require a higher degree of proof that they're not wasting their time and emotional energy, some of which does not reload with time, on someone who sees them as a lay or an option or isn't trying to make it work because of some special feeling of love but because he's settling and the minute someone seems possible to hit what's missing, he's gone or when it comes time to make it more, the compatibility wasn't there so he can't take the big steps.

Meanwhile he's wasted a year or more of her life because he didn't want to be alone.

Someone can be the best lemon cake in the world but if he wants chocolate cream pie, you're sunk. So yeah, if by romance you mean being with someone with no thought of the future, you're right, when women mature and many men too, they want something more, something meaningful, without an expiration date.