These movies are not exactly subtle about which side is the "good guys" and which side is the "bad guys".
Who do you side with in a much more ambiguous movie like Apocalyspe Now or Sicario?
Or, if you're like most movie watchers, you watched Zero Dark Thirty and sided with the American commandos. You watched The Hurt Locker and sided with the American bomb disposal experts. You watched Argo and sided with the CIA.
I'd guess there are a lot more pro-American movies where the typical audience sides with the Americans than there are anti-fascist movies where the audience sides with antifa. In fact, a lot of people who watched Starship Troopers didn't get that it was an anti-fascist movie at all and took it all at face value siding with the humans against the aliens.