We have a 45" from ~2013, I used to connect it to the internet in the early days when I didn't have a Chromecast. The UI is underwhelming, and the only times I've used the smart TV features was when a streaming device wasn't working.
I've gone through 4 streaming devices, and I think that even if I get a new TV, I'm likely to continue with streaming devices, unless that TV runs stock Android TV. Even then, it'll reach a point where the firmware is no longer updated.
Yeah good luck with that. I did the same. Then all the streaming devices stopped working suddenly. Turns out that there was suddenly an HDCP compatibility issue which obsoleted the TV instantly.
I've gone through 4 streaming devices, and I think that even if I get a new TV, I'm likely to continue with streaming devices, unless that TV runs stock Android TV. Even then, it'll reach a point where the firmware is no longer updated.