Not to mention that on all devices I used the official Prime Video app (yes, even Fire TV Sticks), there we massive audio latency issues up to the point where I stopped watching. On FireTV Netflix had also lagging behind audio, which it never did on any other platform.

I am talking about a like 1 second delay here, not 50ms (which is already not good).

Amazon doesn't care about the viewer/user experience. It is always a disaster.