I mean, there really isn't much to this.
A-Rob was a very good WR who in his final year of his contract acted like a ***** and dogged it all season, and at the same time, also played for a completely incompetent head coach who took it out on him and had him running a ton of crossing routes instead of his usual routes.
BOTH are allowed to be true - that Nagy was screwing A-Rob a bit, but also because it was a contract year, he should have showed up on every play so that he puts out good film for the next team, and his lack of willingness to do so shows a severe character flaw that makes you question if he will be able to keep his head in the game when things are tough.
There it is. That's the whole thing. Discussion over.