He didn't "whine" or "trash" the seasons. He indicated that he understood it ("That’s fine. It’s the nature of a multi-character show") and he actually praised the seasons ("As a whole it’s been overwhelmingly positive and brilliant" and "last season and this season there were great scenes"). You seem to be ignoring some of what he said and characterizing the rest with hyperbole to paint him in an unflattering light, all because he had some minor criticisms of a show that you love, which is what seems childish to me, to be honest. I think that he was honest and fair and you're overreacting and not being fair to him.
I think it's less him being rude or trashing the show (he wasn't). Main problem aside (his character is off to the side and doing nothing at this stage in the books), he's not wrong on some things - I would've liked to seen his character react to hearing that LF died.
On some others, I don't agree - him not being the Master of Whispers does mean he lost a huge part of what made him powerful, and now he's "merely" and advisor trying to set up a new network.
My issue with the whole Hill/Varys thing is that people who didn't like the season are taking it out of context, making it seem like the actor absolutely hated the writing, the ending, etc... When the truth is entirely different.
And it doesn't matter that he called the whole thing brilliant, etc... Google Hill/Varys and the first 10 links will all be "Varys actor SLAMS writing", "Lord Varys disgusted with show", and rubbish like that.