[drdaeman]

I don't think anti-abuse systems exist in centralized solutions. If there's some nuthead who's persistent to post their important opinion (or whatever they have to post), the only thing that works reliably is restricting commenting to "friends only". Which should be possible regardless of the architecture, as long as system has ACLs and poster identification.

There are some obstacles (like phone number verification) that centralized systems can benefit from and that are harder to have in a distributed systems because of trust issues - but they're not really working at any scale and only thwart least persistent persons.