Marvel paints with broad strokes, and I don’t think that’s an inherently bad way of depicting violence when you’re movies are marketing to wide audiences.
I think it’s more accurate to say that Mel Gibson doesn’t give care about these characters.
But the devil is in the details, and Marvel’s depiction of violence is nowhere near as brutal as Gibson’s.
Where he goes wrong, though, is where he states that a) Marvel films are more violent than his own and b) that we actually don’t give a shit about these characters.