I think that if you want a modern 70+ inch screen I am not sure that plugging anything into and HDMI input will do it. You need to lobotomize the TV. I could be wrong. I am probably going to explore this to some depth next year.
Depends on the TV brand. I use an LG OLED TV and it’s 100% fine being used as a “dumb” TV. I keep it disconnected and use an AppleTV. I never see the TV’s operating system unless I want to adjust picture settings.
