I also own a Toshiba built FireTV that suffers from those same problems but far worse. Way more ads, much slower interface, and the hilarious part is a hidden power off button in the menus(it's fun trying to turn the TV off without the proper remote).
I'll go as far as to say that you can't complain about a slow interface of a cheap smart TV if you went out to buy it with the purpose of using it just as a monitor which is what you really should be doing. The smart isn't a value add except for being able to use a remote app on your phone especially if you're a HN frequenter. You gotta have computers lying around that can replace all the "smart".
I want it, I can pay for it, it's weird that it's getting harder to do so.
Besides, buy commercial panels. You’ll pay a premium for your premium needs and get a much more robust device in the process.
You got any recommendations?