A simple way to filter out bogus accounts is to require KYC. If an account has been verified, they have greater posting abilities. If they haven't been verified, they are in read only. This seems like it would weed out bots and spammers!
I would be willing to do KYC to keep my account!
Common sense will tell you that KYC in a forum that fights against centralization is mere stupidity and ignorance. You're posting as if you got nothing to lose when your identity is being exposed online. This is a forum, not an exchange site that needs regulations from the government.