Thanks for understanding. Unfortunately, it's not so much longstanding users, but new registrations. My pattern recognition is pretty good by now, so I can spot "fake" users a mile away, but sometimes a real user may pick a name that fits the pattern used by the spammers du jour.
What tends to help is rotating the security questions at registration. These need to be ones that are easy to answer for new people who are interested (even if only a bit) in the DS, but not obvious to google for the spambots.
I'm running dry when it comes to ideas what to ask - once some spammer cracks one of the questions they appear to distribute the answers on the dark web and I need new questions. I'd love to ask the loyal forum members for suggestions.
Please reply by PM ONLY (so that your reply to me remains out of the prying view of google
which would defeat the purpose).