I think your thoughts here are spot on, particularly the need to rewrite and evolve the characters for more of a mainstream audience. One problem with Quantumania was I thought that it was too ‘comic book’ in its approach. One unspoken reason the DC universe never took off was the desire to put inherently camp 1960’s comic characters into these gritty situations and hope it takes off; The MCU wisely sidestepped this issue from the start by basing its characters on the more realistic ‘Ultimate’ line of comics but they killed that line some years ago.
With DC it only works if the actors and characters are in on the joke or they make some attempt to evolve the characters. This is why TV series like The Flash and films like Shazam! And Aquaman work so well but all versions of The Justice League need to be buried in the desert with the ET Cartridges and written off Funko dolls.
I know this may require a more detailed write up than a few sentences but I’d love to know why you think Age of Ultron is sexist. I’m not arguing against your stance (I can see many reasons why it might be) I’d just love to hear it :)