I am in here, working on my debanding for ReShade because even game developers don't give a damn about making things right when it comes to using 8bit graphics.
The only competition there is right now is for TVs, not even TV panels, LG makes the 4k 55"/65/... OLED and no one else still? They all buy a panel from LG to make their TVs. So in the end there is not much competition either since there is 1 source of the actual important hardware. Unless you want Samsung's VA subpar TV.
Mobile devices displays are mass produced by many and at low cost, competition exists and the volume is large in units. You can get cheap displays all the way to expensive.
As long as people keep buying these sub par products they will keep selling them. On the other hand what are people supposed to buy when there are no alternatives thanks to the endless mono/oligopolies.
The monitor display market has been left to rot and die long ago as they moved into mobile and premium TV displays as their main source of profit. They will rather sell 1 overpriced TV than 10 monitors.
What TVs people buy also varies per region. In EU OLED leads and people are not interested in LCD when spending that large amount of money on a TV. In US it's still the other way around.