It’s really not like punching (though cunt punching is also a thing some people enjoy!). Despite what porn might show most fisting is more like getting it in there and then not as much movement. There isn’t really a whole lot of room to move in there! Don’t assume that someone isn’t treating a woman or a vagina with care just because they like to do something different! After all, your kink may not be my kink, but your kink is ok.