Hi! Sorry for such a late response.. I don't log in as much as I used to.
Thank you so much for the compliments! Personally, I don't see there being a wrong way to do art. I can easily see a cartoonist making it far without really studying realistic anatomy. That being said though, I do see the benefits of studying realism before playing around with exaggerating certain features and I recommend all artists, cartoonists or not, to study realism and to really learn about the anatomy. I took a full on class drawing bones and learning about proportions and I feel that class helped me improve as an artist tremendously even in my cartoon work. I even have taken some classes where we draw still life's and that has found itself to be extremely beneficial for me as well. If you look at many famous cartoonists, you'll find that they've mastered realism during their studies. Picasso, for example, did amazingly realistic work before he ever took a more abstract approach to art and I feel that the prior studying of this helped his abstract work feel more skilled and intentional.
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R, I am not gonna tell anyone that they are doing art wrong, BUT PERSONALLY, I'd recommend learning basic anatomy and realism as it really helps push your cartooning and really helps grow you as an artist. That's just my opinion though. :--) Thanks for reaching out. I've loved talking about this.