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.