Even in this poorly made comparison shot I made you can tell the difference between streaming and "self hosting"
(lemmy.world)
Jack Ryan S3 E3
A lot of "alternative sources" are BluRay or even 4K Bluray rips. Of course there oftentimes also are Prime Video or Netflix rips but that just depends on availability. Usually there’s a choice. You can also download rips that are more compressed than Netflix would ever be but if you’re out for quality you just don’t download those unless there’s nothing better available.