I don't know if I really get the point, but I will try and give some sort of an insight of my own, for whatever it might be worth.
First, I want both! Diapers, and the option to play at baby, be treated as such, so on. That said, and to the actual choice, it would be, diapers. I am AB/DL, or consider myself most easily defined under that heading. I have other baby, sissy, adult child related interests, but for simplicity, that heading works. The underling thread for me though, is having diapers. So, my choice to go only with diapers, is a quick clear cut choice.
There have been many times, when I did play at other things, which didn't involve diapers. And these were, non sexual, play type fantasies. (Although, with respect to psycho analysis of such things, sex being why we do everything.) They did not involve a direct sexual encounter. Some of these happen way back in childhood also.
I may have staid from the topic a bit, but my point here is simply, that I have and can play without diapers. I would here and, at this point choose not to.
I would not give up my diapers to be babied.