Calling names without understanding what’s actually going on is always a great start.

“Smart” seems to just mean internet connected. Basically all TV watching (at least in my experience) has moved to streaming, so you need a connection somewhere. Either TVs have it built in (and show you ads in the output selection menu – I’ve seen this) or you connect something else to it that streams content. The Fire TV stick was a cheap way to do this, Fire TVs are cheap TVs that let you do the same.

I’ve been using an Apple TV and capped the wifi connection of my TV, works great and no ads.