It depends upon the man and the woman. Using my wife and myself as an example, it was easy for her to ride when we were first married (35+ years ago), even though I'm a big guy and have broad hips. As we've aged, we both packed on a few pounds and gotten less limber. As a result, it's uncomfortable for her to spread her legs far enough to straddle me now and we have sex in that position less often. Even when we were young, it was easier for her to ride our best friend (who we were in a threesome with) because his hips were much narrower than mine. By the same token, the last girl friend I had before I met my wife could do the splits w/o much difficulty and, as a result, never had a problem riding me. It's all about anatomy and geometry.
Im agree with this. Ride the guy is my favourite position, and with the time and guys with i've been i know how ride a man.