Try to read it again, I make zero assumptions, apart from the 2 you have stated yourself. You want a phone the size of an iPhone 4s but use a S23 Ultra. I’m just pointing out that those two are contradictory.
If I were to make an assumption, it would be that it seems you want a flagship phone the size of an iPhone 4s. Which you kind of can with a foldable.
Battery bypass is not exclusive to the S23 Ultra, the entire S22 and S23 series have it: