I don't think so. This pattern has been observed, and has been a problem, since well before the modern eyeballs-and-engagement-obsessed era of the internet, and before ads were even present on forums at all. What you're describing makes it worse, but even in its absence there is a certain vocal subset of humanity for whom dominating a discussion is its own reward. As a forum grows eventually you will attract one of these people, and from that point on the discourse of the forum will be determined by Survival Of The Loudest.