Agreed. If America goes as crazy for Captain Marvel as they did for Black Panther just because of the fact she's a female superhero, then it will easily gross over a billion worldwide.
Whether the hype of IW results in better sales will be tested next month with Ant Man. If it manages 800+ million than Captain Marvel is almost guaranteed a Billion.
Well, Ant Man is less related to IW (at least for the general audience) so I'm not sure that it will do great, but we'll see!