I never get the “why didn’t Tony/ Cap/ Thor call for help?” question. Why would they? For the same reason most action heroes don’t just call in all the cops and a multitude of back-up. Because it’s personal. Because they think they can handle it alone. That’s just admitting they can’t do the job. Or because they don’t have the five hours it will take them to arrive.Definitely. It's also something the MCU has completely and utter failed at multiple times. Iron Man 3 comes to mind as the worst example. Why weren't more heroes able to help Tony? And why was the House Party Protocol never used again/before? Because it's an Iron Man movie. Civil War also failed in the other direction; it was supposed to be a Captain America movie but was really just Avengers without a couple expensive stars.
BP got this one right in a lot of ways.
Or because their friends are busy. I don’t think we need a scene where fugitive Captain American calls Iron Man only to find he’s busy on his own case.
It’s the same reason the police don’t call and wait for SWAT and the FBI for every call.
Or why every Marvel comic isn’t just Avengers.
Why wasn’t House Party used again? It was at the start of Age of Ultron with the Iron Legion. That and his suits were blown up. He only had a few left.