Just get a cheap PS4 or Xbox and watch all your stuff on there. We have an LG “Smart TV” that just doesn’t need to be connected to the internet because our PS5 (formerly PS4) is fast and snappy, and has all the apps we could want to stream off. Plus, both have a Bluray player installed right off the bat, so we can even watch those if we’re up for it.
Don’t bother with sluggish performance on your Smart TV, it’s just not worth it.