You should absolutely never give your 'smart' television the wifi password or plug it into a cable that will give it a DHCP lease. Use the things as dumb displays driven by an xbox or PS4 or a home theater PC.

Yes, the xbox and PS4 home screens have 'ads' (promoted games and stuff mostly), but they're not 1/10th as annoying in my opinion. And Microsoft and Sony have a much higher likelihood of keeping the operating systems properly patched and up to date on a 5, 10 year time scale.