There are plenty of heroes in the Marvel Cinematic Universe.
Audiences are going to be reminded of that soon enough.
Which heroes pop up is anyone's guess.
But, one thing is certain.
The Fantastic Four are not in 'Infinity War.'
For the Russo Brothers, it came down to money.
All the deals are hard. Everybody's expensive. It's very complicated to put together a movie of this scale. Sometimes, it's easier to say, "Maybe, we should just not do it with these ..."