You're somehow either wearing very pants from me, or you have a very different comfort tolerance.
(This is very reminiscent of the discussion I have with people who tell me they can fit a Nintendo Switch in their pockets...)
An iPhone XSMax is 6.2x3 so it fits very easily. It's only a quarter inch larger than my own phone. An iPad on the other hand is 9.4x6.6, way too big. An iPad mini is 8x5.3, which lets it be crammed into the pocket but not be comfortable while sitting.
I recently overheard a conversation where someone was amazed by a colleagues small phone and wanted to know what it was. "Wow, what is that phone its so small!" "uhh, it's just a pixel." "Aren't pixel's huge?" "Those are pixel XL, this is a normal pixel..."
The pixel 3 is 37% larger in volume than the iphone 5. It is only 15% larger than the iphone 7... gosh but I wish phones release normal+ xl + compact.