Well, how would you display these recommended comments? How would you analyze the content of comments to determine recommendation? If I downvote every anti-Linux comment I see, does the algorithm stop showing me anti-Linux comments? Because that detracts from the debate going on. What if I downvote based on poor spellings - or even more, if I downvote solely based on how well the writer forms sentences? How will the algorithm figure that out?

The easiest solutions are the simplest ones. Complexity only serves a purpose when there's a simple cause behind the complexity. Adding algorithms when there's no need will only make things less reliable.