To be fair, anime studios treat their animators like slaves.
And that is because studios are greedy and they take too many projects or they take a project while being understaffed. And they start production given people with very little time to prepare and they have to keep animating while the season is on the way (which causes delays in some cases).
There's only two studios I know that don't treat their animators like shyt, and the main reason is they have the resources to 1) not rush production 2) have a bigger than average team working on the project and 3) take it one project at a time.
In this case, they've had more than 30 months to work on season 2 of Invincible and they whole process came out shyttier than season 1
Just because Amazon is backing the show doesn't mean its being allocated an unlimited budget. They have budget constraints just like any other show. I think the assumption is that these shows like Invincible or the Boys are hits but there isn't any publicly made information that I can gather on what the ROI is on these Prime video shows. I would say its more likely that these shows are punching above their weight class in terms of what financial investments they are getting from Amazon. I could be wrong.
We are talking about two different things. My point is that it shouldn't be that expensive to treat this show like a good anime studio treats a top project. Say, Ufotable and Demon Slayer or Kyoto Animation with something like Violet Evergarden (which is sappy romance show that has amazing animation just because they can
)