>>530388478
PM has had a dedicated, strong moderate following of autists for a long while now. So they came in with that core base of loyal fans. Now that it's more accessible, more are being exposed to PM's works. Now others that would like the setting, storytelling etc. are getting into it as well. Even when it dips down again, that small dedicated following will likely still be there at the core. Even if it's changed from the start.
Like this anon says >>530388921 it appeals to a specific type of person as well.