Don't get some of the comments. Most high-end screens include "smart" features; if not then it's often a poor model (yes, I have a smart tv).
When doomsday arrives and the manufacturer stops supporting the apps you want, then just buy a little box to connect to the TV (just as you would have to if you had a "dumb" tv). By this time you would probably want to upgrade your little external box anyway.
So your TV can be used for years, at least until the PSU caps shit themselves.
I find it's nice and easy to watch on-line content directly on the TV (in fact I watch very little broadcast stuff these days), but in reality little different to having an external little box. The difference is I get a very decent massive screen.