At least 50% as harsh before his departure than he is afterwards.

How about this sarcastic and brutal bit, on his podcast (end of July):

"But maybe instead of firing him, they start selling pizzas out of the back of Apple stores and Alan Dye can run that and do the graphic design on the boxes. Do the menus. I think Alan Dye could kill that with his Levi's experience, right?"

That's rougher than anything he has said post-firing, in my opinion.

All criticism of Apple’s UI would count, as Dye was in charge of it and ultimately responsible, whether he is named in the article or not.

And Gruber has been at least this harsh on the UI before.