I don't see what's "dreadful" about it: I'm fairly happy I can go do some tourism in the Deep South without fearing getting lynched after dark.

Just to be clear, I didn't mean to get into any race issues, but merely to discuss the prevailing norms of public discourse. In many places in the U.S. a century ago, I can well imagine that spiting the local public opinion too heavily might get you in really bad trouble, including even mob violence. Nowadays this is no longer the case, but such improvements come at a cost. Instead of a bunch of places with different standards in which different things are permitted and forbidden, you get the same standard imposed everywhere. Hence the present uniformity.

Of course, judging these changes is ultimately a matter of personal opinion, value, and preference. If you believe that the ideological standards of public discourse, academic scholarship, etc. that are presently imposed across the Western world are merely promoting truth and common sense, clearly you'll see the present situation as a vast improvement. If you seriously disagree with them, however, you may well prefer a world in which there is a patchwork of places, where in some of them your opinions might get you in serious trouble, but in others you'd be free to discuss them in respectable venues -- even if the present standards are not enforced by any sort of draconian penalties, but mostly by ostracism, marginalization, and career damage.

That said, how do you think the Age of the Internet affects this ideological uniformity?

The effect is twofold. On the one hand, it has given rise to various obscure venues in which extremely interesting contrarian opinions can be read. These are however read by tiny audiences and written by people who are either anonymous or, for whatever reason, don't have much to lose in terms of further marginalization and public opprobrium. Their influence on the mainstream opinion is effectively zero.

On the other hand, the internet is greatly increasing the pressure for ideological conformity, because it has vastly amplified all sorts of reputational damage. Once you're on record for having expressed some disreputable opinion, this record will be instantly accessible to anyone who just types your name into a computer, forever and irreversibly. I think this is the strongest effect brought about by the internet, and it clearly goes towards strengthening of the ideological uniformity.

One also often reads opinions about how the internet is supposedly some big technological game-changer that's somehow going to undermine the traditional institutions of public opinion. As far as I can tell, however, such arguments have never risen beyond sheer wishful thinking.