Who fumbles in the resolutions of 4k TVs?

Question

Monitors

Good afternoon fellow experts!
I have seen a lot of letters saying that playing on a 4k monitor in FHD is a mess, the quality drops compared to a regular monitor.
But what about TVs?
Is it possible to play perfectly on a 4k TV in FHD?
The question is of interest, because I see no reason to buy a monitor, a strong computer, for 2070super, but it will be hard to launch some kind of metro even in 2k, I don’t see a push from the monitor, under which everything else needs to be updated.
Now I play perfectly on a TV set, some very old Samsung, but I'm thinking about buying some kind of 4k from xiaomi.
Help me to understand.

Answer 1

if you play fhd, then you absolutely don't care fhd you have a TV or 4k.

Answer 2

I think it all depends on the TV model.
My Samsung any video stream with resolution up to 4K dynamically upscales to 4K.
Games from 720p look more than good.