But he's saying so while filming Avatar 2, 3 and 4. Very high level of hypocrisy. And he didn't complain about blockbusters but about superhero movies only IIRC. It's easy to understand him. The interest for Avatar sequels is already low, so he wants less competition to lower the flop chances. The only marketing plan for Avatar 2 so far is "the sequel of the biggest movie ever", it would be awful for him to lose that...
Actually, he'd be right either way. DC movies have been doing great, but everyone calls them a flop because they aren't the Avengers. Naturally, some people start getting annoyed when the bar is set at "the most popular franchise to date that is clearly overhyped".
I liked the MCU for a while, then Civil War happened and I rage quitted. Given how GotG went, I was probably doing the right thing...
Hint: Splashes of humor are alright. Enough humor to get a Comedy tag isn't.
Well, we have different tastes. I watch MCU movies to have fun. And for me, laughing is a way of having fun. So I love movies like GotG or Thor Ragnarok, in which you have jokes, fights, a bit of drama, and then once again jokes and fights. If I want to watch something serious, deep or thought provoking, I'll watch something else. MCU movies are IMO the perfect "fun to watch" movies.
And DC movies are called flops both because their BO is a lot lower than MCU, and because the movies are also pretty badly received for the most part. It's as usual in comics a "battle" between Marvel and DC, and if Marvel wins, then DC loses. That's the usual image.