Not the original commenter, but I'm going to go ahead and assume he meant that the forum has no place in the traditional 'bread and circuses' used to control masses.

Free exchange of ideas and healthy debate mostly yields good philosophies or slight enlightenment of people participating (and when they get back home they bring that with them and spread the enlightenment), though one should consider whether these romanticized versions of the pub and the forum are actually in line with reality. In order to have a good debate you need the right people and the right place.

I would assume that the base example would be workers gathering in a pub and thinking 'what if none of us works tomorrow? who's going to build their stuff?'. And some might not have even thought of that before. And this leads to unionizing.

Contrast that with a platform like facebook that channels you into a place where you find what you already know and think you want via algorithm, and thus are basically shielded from knowing stuff you don't already. Knowledge is power and all that. Sure, the forums and pubs are fairly easy to poison, but it takes more effort.