> anything under about $500 isn't worth trying to sell online anymore

Anything under say $100 I'm fine selling on ebay because a) it's less likely to be scammed and b) even if it is, I don't care that much. Anything over that amount is only being sold in person on fb marketplace. Or, like you said, on a hobbyist forum.

I agree that ebay has completely eroded for sellers. It's basically a ship and be pleasantly surprised later situation.