the only wining move against spam is to make it easier to clean up than it is to spam.

captcha only benefit google and the like, who couldn't care less for the community or content. Captcha makes honest content (and spam cleanup) more expensive than the spam! it's a losing proposition that only looks good when you look at it without considering all the situations.

make honest content (and spam) easy, but cleaning up easier. Things like every user can flag something, after a certain number of flags, also remove other content from the same IP (or same bundle of users with a close registration time window) automatically. And of course a feature for admins to automatically ban and erase content from users wrongly flagging honest content.

It's harder than captcha, but it is an actual solution. Captcha is lazy and ableist.