It's not nitpicking if it's major parts of the story. They messed up their main character's story. This is supposed to be the culmination of the series and they went contrary to past major events from the other movies... It's bad writing. They didn't stay faithful to Captain America's character or arc. He already learned that Peggy got happily married and had a family in, but he still went back to go hijack her life?
In reality this story was over because Steve had accepted that she moved on and had a happy life. To go even further, in Age of Ultron Wanda gives him the vision of what his life would be like if he stayed in the past and it even showed him having the dance with Peggy, but at the end he
still says that he doesn't want that life anymore and that being in the future is his home
They couldn't even stay faithful to the ending of Infinity War where he sees his lifelong friend Bucky disintegrates in front of his eyes. You would think that would be his motivation in Endgame since they actually still have a relationship with eachother and Bucky was a major part of why Steve and Tony were even fighting in the first place...
In what world is this nitpicking. I haven't even gone into the awful plot of the movie.