Dogma & the web

The internet is supposed to host and foster a diversity of ideas. This seems to be true for the early stages of a discussion, when an issue is raw and an authoritative take has yet to be established. 

But conversations seem to become more polarized once buzzwords are exchanged and hashtags develop. These social tools sure can amplify long-neglected and silenced voices, but they can also crowd out divergent views. Must it be that the overturning of each dogma lends momentum to the coalescing of a new one?