Depends on the instructor. And no boob remarks, you louts!!
My wife and I take a "gentle yoga" class at the gym. I think it really does help flexibility. Little things like crawling under my desk to trace computer wires are no longer as daunting as a task as they were. I'm 64 yrs old.
But some of the moves the instructor makes just seems impossible to follow. But that gorgeous young tight body of hers seems a lot more willing to go into some of those positions than my worn out body is capable of. See, no boobs mentioned. (oops). But hers, though small, are awesome in that yoga outfit. And I gotta say, it does make the class more interesting.