[ktpsns]

This is the reason why I implemented rather dumb but individual, hand-crafted captchas for my own websites in the past. Things like input fields which must be left empty, silly multiple choice questions only humans could properly answer at that time, etc.

I have seen communities to implement their own captchas with domain knowledge. For instance, math/STEM people showing captchas with rather easy calculus tasks (such as solving a definite integral). This can be fun to solve and as a human you feel valued. It is this handmade feeling of the "old internet".

The problem with self-made captchas is that even them are rather easy to solve nowadays with LLMs and thelike. Therefore I don't believe that decentralized individualized captchas are the solution as they tend to be rather simple.

[CM30]

The issue is that AI bots can answer pretty much any captcha that isn't ridiculously obtuse. Your homemade captcha can be solved with an LLM, but so can the latest version of Recaptcha or whatever.

But I feel that there may be some other tools here. Spammers in general tend to be fairly predictable in their behaviour, so tracking that could help. If a member is including links to a third party site in dozens of messages, that should be a pretty big hint that their intentions are questionable. If they blast through the registration page in seconds, same thing.

Personally, I've not seen more than a single spammer on the forum I run for the last 6 months or so, so I'm still optimistic that most don't bother unless it's easy to attack and worth their time.