>>51307Fanbox importer has been dead for months, but when it worked it was well-used, with frequent updates of many artists. I myself shared many. Subscribestar importer has been dead for much, much longer.
Anyways in regards to the OP, most artists don't go to Fanbox or Subscribestar because they're stingy, they go there because Patreon has content restrictions. Patreon, as I understand, makes a creator the most money, compared to similar subscription sites. Most creators this prefer Patreon, and only go to other platforms if their content is not accepted on patreon.