I have a 2017 sony 65" android tv, and a 2018 TCL 75" tv.
both suck at android TV. if they upgraded to android 8 they would be a lot faster (my 55" 2017 sony was super slow on android 7, then upgraded and became way smoother/faster).
I personally would recommend an LG tv, the webos3 is a lot faster, it basically turns on straight away with no boot up time, has most apps you need. if you want androidtv (cos it is cool) get a box for it (mibox, or nvidia shield tv). they dont seem to put decent hardware in the tvs to run androidtv, which is a shame.