It's unfortunate that each streaming silo will probably never allow their content to be streamed to a client like Plex. Amazon Channels seems to have not had a great run from what I've heard (IIRC some services left after initially being part of it) so I have little hope of Plex being able to swing something similar. Apple TV (The app, not the device or the service, terrible naming) is just a launch board to kick you into other apps which is slightly better than having to navigate multiple apps but only slightly. I understand it's because the streaming services want to "own" the experience (and all that data you generate while moving around and using the app) but I hate it.

Personally I watch all of my content through Plex because I refuse to switch between multiple streaming services. I'll gladly pay (and I do) for access to the platforms but I still only watch through Plex because I prefer having 1 UI/UX to deal with. I never have to ask "How do I get the subtitle selector up?", "Does left/right skip forward 10/15/30/60sec or does it start RR/FF?", "Where does this streaming provider let you configure X?", and the list goes on.

Spotify effectively killed piracy for the vast majority of my social circle but TV/Movie piracy is still the best viewing experience by a long shot especially with *arr-type apps to automate it all for you.

Money isn't the issue, experience is. It's just like years ago (or it's probably just as bad now but I haven't had to deal with it) when it was better to pirate a movie than get it via Redbox/Blockbuster because you weren't forced to watch ads/FBI warnings/etc.