I believe the big manufacturers don't want to make a small phone (as other users have indicated) because of the big screen's addictiveness. Also, they can't fit a large battery in them so battery life would be a few hours with 1000mp 16k cameras.
I'd rather carry a 1" thick, 4" tall phone than a 0.3" thick 8" tall phone. No pants pockets look normal anymore, and it is even more awkward to walk with tight pants.
You can believe whatever you want, but it doesn’t make it true. We know exactly why they make larger devices and it’s not a secret, it’s what consumers by and large want. It’s not a conspiracy.
Every time a vendor falls for the “we want small phones” thing, they sell poorly thus proving the point again and again that it’s a minority at best that are interested.