Try TCL. I just got a second one after 6 years with a previous model of theirs that was showing signs of death. On both this new (Google-based OS) and old one (Roku-based OS), I have done the steps I mentioned above. I wouldn't have bothered typing that up if it didn't work.

Turning a HDMI device on wakes the TV and then it automatically selects that input. I've never been to the homescreen except by choice, and even then it is completely stock. Barebones, no ads - it has no internet to get any.

Thanks for the recommendation! I'll check them out.