We have a family Samsung smart TV that is configured to use my Pihole instance as its DNS. When it was first set up, it looked up a blocked Samsung domain every few seconds whenever it was on (this is with ACR tracking “disabled” in the settings). Now it doesn’t anymore, but I still get activity from its IP address looking domains for NTP and looking up Samsung domains not blocked by my blocklists, but much less often now. Weirdly, it isn’t looking up domains for YouTube anymore despite us watching videos on the included app. Could it have found a way to bypass my DNS server (maybe a hard coded Samsung DNS?)
(The TV is my parents’ and they want to keep using the smart features. If it were up to me, it’d be barred from our Wi-Fi by now.)
LCD (NOT OLED) and high refresh rate. That is all you need to care about.
Essential extras would be anti glare (get a 3M film if glossy) and white balance. And go for a reliable QC brand (like LG, BenQ or Dell).