Exactly. A lot of streams are just left to rot, either because they aren’t under the maximum users following a stream for it to be deleted or because those users forget.
What imgflip should be doing is removing streams not in use. This incentivizes people to keep posting in the stream, thus generating more traffic for the site. Furthermore, there is a massive backlog of public streams no one posts in. Most of it doesn’t take up much data on it’s own, but I think deleting half the streams that haven’t been used in 2 years could be worthwhile. Someone can always make them again if there is a big enough community to.