I'm somewhat ambivalent about this. The Internet makes it much easier to find like opinions, but that capability can be used just as easily to reinforce existing biases as to dissolve them, a privilege previously available only to the cultural mainstream in a given region. That does make forming or belonging to a subculture a lot easier -- and the Internet seems to be pushing out mass culture in its ~1945 to ~1995 form, as a result -- but it's not as easy to conclude that it makes people's opinions on average any more adaptive.

I suppose we can expect a polyculture to be more resistant to infection, at least. That's a plus.