If Mycroft Holmes forced Team Cap to watch Tony's movies, it wouldn't make any difference
Supposedly Mycroft and Tony are somehow related while Dr. Strange and Tony are raising Peter. I'm not exactly sure what this was supposed to accomplish. While it's unfortunate Tony suffered in captivity in Iron Man 1, it doesn't change the wrongness of his actions before and after Afghanistan. And as far as I know, RDJ's Sherlock Holmes was pretty much like Iron Man, a jerk who thinks he's above everyone else.
***
Team Cap had experienced some adventures and odd happenings in the last few months, but this was simply bizarre. They'd investigated a report of someone selling alien technology. This particular criminal was apparently living out his obsessions.
The team was currently "trapped" in a movie theater, listening to "Mycroft Holmes" explain that Tony Stark was actually his younger brother, "Sherlock Holmes." Then "Mycroft" went on to complain about how horribly Team Cap had treated his "poor little baby brother."
Natasha had hacked the systems before they even sat down. Sam was gently trying to question "Mycroft" to figure out if the man was delusional, criminal, or both. Wanda and Steve were kicking back and enjoying what looked to be an easy mission.
"Mycroft" had then screened scenes from his "brother's" life. The movies were truly awful, starring someone who acted a lot like Tony--abrasive, reckless, superior, and uncaring about how others were affected by his words and actions. "Mycroft" DID look a lot like the actor playing Holmes' older brother, just as the star looked like Tony Stark.
Their captor was NOT pleased with Team Cap sharing sarcastic comments about the events on screen. "Mycroft" stamped his feet and yelled about how they were just ingrates who didn't understand the demands of true genius.
Suddenly the doors at the back opened and a group of henchmen came in dragging three rolled-up carpets. The unrolled them dramatically to reveal Tony, a teenager, and another man with strange facial hair, this time with gray at his temples. He was wearing a cloak that seemed to keep rippling even after the rest of their clothing settled.
"Mycroft" said, "Now my brother, his husband, and their precious son will make you show some respect!"
The newcomers looked around. Then the teen said, "If you're talking about me, I've never seen Cloak Guy and I'm not exactly buddies with Mr. Stark. Plus I already have someone who acts as my parental figure and it's DEFINITELY not him."
The man with the cloak said, "Ah, Captain, Ms. Romanov, Mr. Wilson, Ms. Maximoff. I believe we need to discuss some ways to prevent an upcoming catastrophe. I want my universe to fare better than the last one where I crossed paths with Tony Stark."
Tony frowned and said to "Mycroft," "Don't you know who I am? I am NOT someone you hit on the head and roll into a carpet!"
"Mycroft" said, "Brother! Your words wound me. After all I have done to make your case before your teammates."
Tony eyed "Mycroft" and said, "I've never seen you before in my life."
"Mycroft" suddenly turned angry and said, "Perhaps I'll be the LAST person you see."
He suddenly pulled a gun, but a red mist surrounded his and his henchmen's hands as Wanda plucked their weapons and floated them into a pile at her feet. She said, "I think it's time we exit."
The others turned to leave. The man in the cloak said to Team Cap, "I really do need to talk to you. You can all come to my house for dinner." His cloak seemed to ripple as if agreeing.
As Team Cap agreed, the teen said, "Hey, think you can drop me off on your way home? I'm not really sure where we are, exactly..."
Tony hurried to another exit, determined to get away from "Mycroft" and the others before they could grab their weapons. As he took a last glance at the big screen, he shuddered at the sight of someone who looked a lot like him in yellowface.