Why do some actors do this?
De Niro is now a meme laughingstock, nobody would seriously think of him as a "great actor", except total plebs, simply because he was in so many bad movies in which his acting performance is average at best, that it outweighs all the great roles of his life.
Why don't they know when is a good time to retire?
Or at least be more picky about the roles you choose?
When De Niro dies so you really think people will be talking about the shitty comedies he made when he was an old man? They're be talking about Taxi Driver, Goodfellas, Godfather pt 2, Raging Bull, Heat etc. Welles and Brando ended their careers doing absolute shit like the Transformers cartoon and Island of dr Moraeu, they're still regarded as good actors.
De Niro honestly doesn't give a shit. He's taking easy paychecks and doing what interests him because he knows it'll be a footnote compared to his 70s/80s work
I agree that it's cozy. There were some strange plot directions though, the main one being that they were setting him up as being the new ceo but it never happened nor was it even mentioned.