Nope, demographics of Comic Books hasn’t really changed much.. the pandering is more politically based than demand based.
Editorial Control would be driving shift for demographic needs, that’s not what’s going on with Marvel... they literally loosened up editorial control and let writers do whatever, and of course they started to just ignore decades of cannon and invented craziness that has alienated audiences.
DC has had far more editorial control and you can see pandering attempts to expand demographics there, but NOTHING like what Marvel has been doing... they literally are kind of where DC was during New 52, only worse. They have had things like The Beast from Xmen’s powers are Cat based... not primate/gorilla based... etc etc.. Its a fuster cluck on ever level and utterly unreadable even without all the political pandering.
DC has its share of political pandering too... Batman is almost unreadable and unrecognizable...its now a bat group, including the obligatory female dyke.... Clayface is now a good guy???? Basically as soon as it hits issue 1000 I will be dropping detective. Action Comics with Superman hasn’t been as bad with the pandering, but its definitely not strong... after the new 52 fiasco they now have Luthor a good guy, and even brought back Krypto the dog????
The worst flat out pander though has to be the New Green Lanterns, because you know 3 green lanterns from one planet wasn’t enough, we now have a muslim with anger issues, and a latina women with anxiety issues as the main book lanterns and they are simply rehashing long told storylines.... I will give this book credit that the secondary characters and villains have been interesting (far more interesting than the purely token main characters).... But honestly they could kill this twosome off tomorrow and I wouldn’t bat an eye.
Hal Jordan and the Green Lantern Corps seems to be about the only book that I currently read that seems anything close to “normal” these days. Though it clearly suffers at times from lesser quality writing than others, and some inconsistencies in the characters that editorial control should tighten down on.
I didn’t mean the demographics of comic books changing; I meant the demographics of the public in general. For example, I doubt “Harry Potter” would be as big today as it was originally because there are just less “reading” children in that target demographic today.