MS Paint: Do I really need to explain this? Nearly all of the MS Paint "art" look like they're drawn by either 3 year olds, or by adult children with no artistic talent.
Uncanny Valley: Ever heard of butterface?
Chibi: Even if the males had facial hair and muscular bodies, and the females had 40FFs and pubic hair, they are STILL as small as an actual toddler.
Those are my 2 cents on these types of fan disservice.