It depends on what your aim is. Had Ello followed a proper nonprofit structure from the start, they could have continued indefinitely with a small staff and volunteers maintaining an open source code base and handling moderation. It would not necessarily be easy, but it would be doable.
They didn't though, and the fact that the original CEO later got into into NFTs and now something-AI maybe shows he was something of a bandwagon-jumper. Back then everyone wanted to be the next Facebook, so that was what he jumped into.