Well I'll guarantee you that a .45 that size won't be anywhere near as easy to shoot and control and the felt-recoil will be a lot more
"existent"!
There is something to be said for control and shootability.
A hand cannon for blasting away at point-blank range is fine and dandy but if you want to take aimmed shots and have a chance at accurate follow-ups they just don't cut it.
Plus I like to shoot any weapon I carry, a lot!
Big honking calibers in wee tiny little pistols are brutal to shoot and not conducive to lots of range time and plinking.
Different strokes for different folks, we all have our priorities.