Yeah well obviously none of this basic Marvel flicks are dethroning any titan of film history adjusting for inflation. In fact adjusting, Titanic is also bigger than Avatar.
And this is in the USA. Worldwide the difference is bigger.

This is a tremendous success anyway. I would have loved it if it had happened to a quality film and not yet another generic sequel, reboot, cinematic universe entry type of flick. All of them always with teh same basic plots and never taken seriously in serious circuits. As it should be. But it is what it is. Masses love basic.