Unfortunately its even earlier meaning still has confections to describing special needs people in formal medical terms. In that retard = slow, retarded = slowed. And of course the other meaning like flame retardant, to slow fire from spreading.
But you’re right that it shouldn’t be a slur.
Wait we actually have freeze peach here? Aren’t we also actually moderated lmao (except for that tankie instance but they typically get defederated anyway)
Fuck this guy for lumping the Fediverse with the other crap.