That is demonstrably not true.
If you run Jellyfin and pirate using thepiratebay and yandex searches, you can get 4k 7.1 audio shows.
Why would I pay to be abused and treated like a potential theif if I pay for services, but if I pirate I do get the best quality and experience?
If the company's paid experiences were top notch, I'd have stayed.
But it turns out 40TB, 20 cores, and an Intel Arc for high speed transcoding easily handles 200 shows, 3000 movies, and more. And the big upside? No more 'killed by Netflix' or trying to figure out what streaming platform has THIS show today.
My newer 4K controller started acting up recently and I had to ifixit.
And how usable are they if you're outside of the Apple ecosystem (i think I saw an article recently that someone was stuck and needed to use a mac or an iPhone to get unstuck).
But, as far as Roku they are subsidized by selling your data and pushing ads as you call out above. Not really a fair comparison. Just like you have to pay more everywhere for the ad free tier you end up paying more for Apple TV.
I will say though that the Apple TV handles 4K flawlessly. I am willing to bet that it has quite a bit more power than any of roku’s offerings.
If you go to the trouble of setting up a media server and Kodi/Plex on the TV, and install a barebones launcher that avoids all the ads on the official launcher, the remote still works well. I don't know whether to blame Sony or Google but every system update brought bigger and bigger ads to the point that I took an afternoon off to sideload an extremely plain ad-free launcher.