It's unclear to me why we'd be optimizing solely for pixels or pixels/$.
I personally like my wide monitor, and I don't even particularly care to go for more pixels when available, ie my preferred resolution is ~1440p. They're nice and cheap, they look good to me, and they're easy to drive for the gpu.
I go more for deep blacks and good colors, pixels just look good until your eyes adjust and then it's all the same.
For me, it's about screen real estate, not looks. More pixels is more usable space, until you have to start scaling things up for comfort. I find a 27 inch 4k monitor to be comfortable without scaling, but I think it's just about the limit for me, and I expect that the PPI limit varies from person to person.
I personally like my wide monitor, and I don't even particularly care to go for more pixels when available, ie my preferred resolution is ~1440p. They're nice and cheap, they look good to me, and they're easy to drive for the gpu.
I go more for deep blacks and good colors, pixels just look good until your eyes adjust and then it's all the same.