This is one of the problems with online conversations in general. Person A makes a lot of low effort comments without putting much thought into it and without bothering to check the accuracy of what they're writing. Person B thinks about whether or not they have anything to add to the conversation, spends time thinking about other people's comments, checks any claims they make to see if they're accurate, rewrites their comment so that it flows better, etc. Person A is going to end up making many, many more comments than Person B. The conversation will look more and more like Person A's posts, even when those people are in the minority.
There are some places that suffer more from this than others, but I think it affects just about every online conversation to some extent. It would be interesting to see what effect posting limits would have.