Respectfully, I think you are the one who is missing what is actually happening here.
The audience for the comic book movies, (etc) that are being race & gender swapped are still overwhelmingly male, and to a lesser degree (but still mostly) Caucasian.
The character swaps are not designed to broaden the audience, they're happening for ideological reasons.. which is to proselytize & lecture the audience they know is majority male (& Caucasian).
A perfect example was the recent She-Hulk series. Some male viewers were upset because in the finalé, there was a patronizing depiction of male comic book fans as petty incels. That stereotype wasn't inserted to recruit/"target" more female viewers, it was a direct insult transmitted to the audience they know is overwhelmingly male.
For you to believe all the ethnic & gender changes are for audience expansion, is a pretty naive and generous attribution.