The 1990s John Woo movies were over the gun in their gunplay (The Killer, Hard Boiled...) but there’s far more violence in the Capt. America/Avengers films (which is the one where everyone at the CIA/FBI/oh yeah SHIELD is a Hydra-NAZI?).
When they stopped having to wire up squibs to do gun stunts (and switched to computer animation) they amped it up.
Is the lack of blood “less violent”? Is shooting people in the kneecap less violent than shooting them in the chest?
Well, a few decades ago, someone would point a gun, there would be a BANG! and the bad guy will fall in a heap. Pretty simple, neat and quick. It represents a "death" certainly, but the level of "violence" was pretty minimal.
Today, people get their brains blown out, bullets enter the chest and blow out through the back. There is blood, there is screaming, and sometimes you need to pump in a few extra shots just to be sure. It's kinda violent.
Also, in the old days, the Good Guy would often just "shoot the gun out of the hand" of the bad guy. I suppose that stung a bit, but by disarming the evil-doer the hero would Right the Wrongs without bloodshed.
Of course that's silly, but that's pretty much the point. It's a family-friendly cartoon which you wouldn't try to replicate down at your local High School. But in today's movies, you can unleash Hell on all of those who "have it coming". This poisons peoples' outlook. It is inherently different from the stuff I grew up with.