Go back to selling "dumb" sets and I'd buy 4 brand new, big TVs right now. Seriously, I would replace both of my existing TV's and finally get ones for the other major rooms in my house almost immediately. But I won't, because all you can get now are smart TVs and smart TVs are just fucking awful.
I wouldn't mind basic TVs being sold again, but you can just buy any smart TV and not connect it to the internet in order to have the functional equivalent of a dumb TV. I always just use Rokus or other external streaming devices rather than the constantly out-of-date TV streaming apps native to the TV itself.