Is LCD TV screen technology unsuitable for regular use on a computer monitor at close viewing distance?

We ran a very informal experiment at one of my former workplaces (software engineering) by passing around a couple 37" 4k TV screens that people tried out as monitors. Anecdotally, some people got super ill feeling using them, and some people loved them, there were too many factors to narrow it down beyond that but it was certainly more people that couldn't use TV's as monitors than monitors as monitors.

The LG 24LJ4540 would make a poor computer monitor because of its very low resolution and pixel density. There is nothing you can do to fix this.

This monitor has a 23.6" (diagonal) panel with 1366x768 resolution. That gives it a pixel density of 66 pixels per inch. Put another way, it has 4409 pixels per square inch.

Your Dell E2020H has a far superior pixel density. It is a 19.5" panel with 1600x900 resolution. So it has 94 pixels per inch, or 8863 pixels per square inch.

This is twice the number of pixels per square inch as the LG 24LJ4540. So everything on the screen is sharper and more detailed, causing less eyestrain.

Now of course this all depends on your eyesight. What distance from your eyes do you place the monitor, and do you have trouble focusing at that distance? Don't use the monitor to test this, take some printed text with very fine print and see if it is easy to read at your monitor distance or not.

If it is hard to read, it may be time for you to get a pair of single vision prescription glasses, adjusted for the distance to your monitor. Let me know if you have the budget for that and I will update with some specifics. Also let me know if you only use separate monitors like these, or if you ever use a laptop with its own internal display.

I hope my questions about your eyesight are not too personal, but I see so many people squinting and straining to read what is on their displays, where a simple pair of prescription lenses would fix this. It was a revelation when I got my first pair; I wished I'd done it years earlier.