Are you suggesting Gruber is upset at Dye for leaving Apple?

We all disliked Dye before he left. People were taking potshots at Apple's design direction under him for 10 years.

He thinks Dye was never good enough to be at Apple and that he would think of leaving proves it

Is there something you perceive as unfair about judging a guy on the output of the work he was responsible for over a long period of time?

You will note that this is not what is being judged as I described in my comment that you just replied to