Lemmy fulfills a sort of reddit/more intimate internet forum thing. Reddit's real social good was fixing shitty search engine results by using Reddit as a keyword, and for centralizing a lot of hobbyist discussion. Lemmy and the lemmylikes will get there as the platform matures.

I'm loving pixelfed as a sort of Imgur substitute tbh. Quick and easy image hosting for when I post on here. Not crazy about Instagram as a social media platform so there's nothing I need pixelfed to do besides let me host medium-sized images, caption them and copy the link.