Is it about power and degradation? Not usually. Believe it or not, it can be very pleasurable - for men and women.
Any hole is a goal - not for all men. It's about the person and and their body. It's like saying that any woman would be satisfied with something that resembles a cock. Many straight women would have no desire to get fucked by a woman with a strap on so...
Hygiene: anal douches are simple to use and if she likes anal then she's going to be fine with that. And...condoms.
You don't have to understand it and you don't have to try it if it's not your thing. But for some of us it. You do you, boo. And if you really want to know, try it with a woman that's open to it. Or a dude if you want. Try it with someone you love. It can be really intimate. Or don't. Your call.