The pixel density, among other things, are very different between a TV and a Monitor. This is why a monitor of similar size will be vastly more expensive than a TV - they're optimized for different viewing experiences/use-cases.

For a simple example, a TV usually assumes the viewer isn't sitting just inches away from it...

There are differences but man you for sure picked the most incorrect one - 4K say 42" OLED TV and same dimension PC gaming screen have exactly same pixel density, there is no subspace magic.

I have a 4k 42" OLED Phillips Evnia monitor on my desk.

If they sold a 4k 65-75" version of it, I'd buy it in a flash.

https://www.philips.co.uk/c-p/42M2N8900_00/evnia-gaming-moni...