That must be laughable quality. 1080p blurays easily clock in at more than 22Mbit/s for grainy content, the spec allows 40Mbit/s. And that's not even including the audio. UHD discs must deliver at least 82Mbit/s.
And a lot of content is not even using the things that UHD standards allow to deliver (4:4:4 chroma instead of 4:2:0, higher framerates). So even if they're delivering in HEVC is suspect that the compression is not source-transparent.
Streaming services really frustrate me for that reason. I get that bandwidth costs money but when e.g. Play Movies advertises a movie rental for $5 but when that actually means $5 for SD (who the hell even uses SD) but $10 for UHD when it's compressed to shit, what service are you actually providing me?
'Well, turn it on!' is certainly one solution, but of course enabling JavaScript doesn't just let me view images (something HTTP & HTML do just fine anyway), but also enables execution of potential malware, tracking & other nastiness.