I've fixed the main page discord link.
Main problems with activity that the mods will strike down anything that looks like characters(ie, factions or companies), we've been placed into a section of the forum not for KSP,(I've tried to appeal that), and there was a mass bleed out in 2018 as a result of player shift towards KerbalPowers.
EDIT: oh look we got moved to challenges, guess that can be removed as a reason. Activity also tends to waver without any sort of youtube series to drive it. The two larges blocs of activity were around Spiritwolf and Kethane Station submissions opening.