I've been using https://metapixl.com for a while, (well, not really using because I have nearly zero use for it, but anyway), I think it's a really good one since it has the most generous resources of the ones I looked at over on the Pixelfed instance finder.
From what I've seen so far the whole place looks like a ghost town though, or maybe it's just me not having experience with interacting on Instagram-like software so it seems like the activity is barely existent, nearly no likes nor comments anywhere I look on average, however there are quite a bit of posts!