>>32834873/vp/ is a cesspool of toxic masculinity.
As another anon pointed out, plenty of users seem to only be able of interpreting designs in two ways: cool "bro" mons, which usually display masculine or genderless traits, or "waifus," which are feminine.
Because of those users' insecurity about themselves, their bodies and their sexual prowess, they tend to idealize the more masculine "bros" while mocking the more feminine designs. By doing this, they reinforce to an anonymous image board their masculinity, and assert their heterosexuality by lusting over designs that skew feminine.
Decidueye has gotten so much hatred for being called a numale. Anons have, for some reason, projected a school shooter persona onto it and spew hatred toward it, but the bottom line is it probably just reminds them of themselves.
It's fucking embarrassing.