On the bright side, those believes help us identify undesiderable men. I mean, you can lie and said that you have a high body count and just let them run. Or pay attention to the fixation with 20 something to avoid them.
Sometimes it pays to pretend to agree so they talk about those things, pay attention and ghost them the second you identify them. You are not going to change their mind, but you don't have to date them or have any kind of relationship with them.
I mean, look at JenLo and Shakira, I'm sure none of them care about those men not finding them attractive while filling concerts and going out with younger handsome men without a problem. Well, same with other unknown women. They'll enjoy their lives and doesn't have to deal with those idiots anymore. All advantages. XD