... the largest class of pests comes from the insect class.

I think they cannot compete with really biggest 'pest' on earth: in my eyes the most destructive animal on the planet is called Homo sapiens ... or did you ever see locusts pollute environment with smog, plastic or nuclear waste, destroy forests or lead wars? :)

By the way, as you asked, there is a community Discord which you can find at the startpage of "Fascinating Insects".