I don't think I'm an "average" customer at all(but then, maybe no one does), and I would hate to own a dumb TV. We have an LG CX with all the apps built in, it's super convenient to have everything just built in right into the TV, to be able to control all of it with just one remote, to be able to cast directly to the TV from pretty much all of my devices. The TV and the apps start up pretty much instantly too, I have no issues with the responsiveness of the entire system.

Yes I am aware some "smart" TVs are incredibly bad(I wouldn't buy a Samsung having read the reviews of many different models) but yeah, having a dumb TV+ extra devices just to stream to seems like a hassle.