Eh, if you’ve got a prostate (aka you were AMAB) that’s probably doing most of the work so ribs likely wouldn’t matter. If you’ve seen toys designed for anal they often involve much more dramatic texturing (i.e. anal beads) since that will trigger a sensation that ribbing likely won’t.

And, if you think about it logically, if you’re constipated you kind of don’t want to feel every minor fissure or bump on what’s coming out.

So as an AMAB I haven’t observed a difference and I kind of doubt AFABs would either.