I think what's happened to comics is a prestige bias. the better selling comics had small waists and big boobs, so the other artists saw that and figured if they exaggerated those characteristics, they too could sell well. not saying its a good thing, just what happened I think.
I think that you’re partly right: what you’re saying reminds me of something my husband likes to say when critiquing some hard rock and heavy metal. “Wow, that Jimmy Page guy is fast, and loud, and good: if I’m faster and louder, I’ll be better!” Yyyyeaaahh no.
I also think that there are a lot of comic book artists who did not actually learn their craft in school or receive formal training of any sort. They learned comics by reading comics and copying comics, and it’s basically that their POV in their formative years of comic book training was limited to what they saw on the shelves. And if it’s published, it must be good, right? That must be the correct way to draw.
As far as I know, there aren’t that many schools that offer a comics program, whereas it’s far easier in comparison to get an animation education. Arts programs in school are perceived as forming only the fine arts people of the world, and you have to look for the specialised programs in book illustration, graphic design, advertising art, and other commercial applications of art.
Hey, even I don’t have a formal training in animation or art, I learned most of what I know on the job, but that’s another difference between the animator and the comic book artist. Animators more often work in studios, surrounded by their peers, where they can easily get feedback, learn new techniques, have the kind of job that trains them to take on a more senior or complicated job, and have a director who overlooks the whole of the show/film/ad/short and really can bring a team together to get a better final product. In comics, many artists work from home or in private studios, by themselves, and I have to wonder if many editors actually know how to draw, and how many drawing revisions are sent back to the penciller. Pages are mailed or emailed to and from the publisher. I guess that because it’s a much more individual work product, there’s less of a need (or more of a reluctance) to edit and fix to fit an established style than in animation. If I were a comic book editor, I think artists would hate me, because I’d be redlining their stuff… just like my stuff’s been redlined by directors when working on storyboards.
I’m rambling. To recap, I believe it comes down to lack of formal education, and limited scope of material to learn from.