Most TVs have some weird effect where it just puts white dots in the middle of the strokes of a charater glyph.
However, I've seen several Samsung TVs which doesn't suffer from this phenomena and can be used as proper monitors.
For coding purposes I don't think color accuracy matters much, but I see why latency might annoy some people, though it doesn't bother me.
on my seiki tv's you can remove that by setting "sharpening" to zero.
probably could do that on the samsungs too, burried in the menus somewhere.
I use a 43" 4k TV as a monitor and it's great. It's on the outside range of size due to the 100 ppi pitch.
You're referring to chroma subsampling. Rtings does a review of 4k TVs that support 4:4:4 chroma.
https://www.rtings.com/tv/reviews/best/by-usage/pc-monitor
This page also has a link to their subsampling article.
1) Input lag. A mouse 200+ms behind is frustrating to work with.
2) Color space. I forget the terms off hand, but basically if the panel has poor colour space / bit depth / whatever, fonts start looking really bad.
Maybe you lucked out or just don't notice/care about these, but that's one of the core reasons people don't use TVs.
I'm quite tempted to get a large good one though.