Then pick a different medium. A single tabloid doesn't tarnish every single news industry. Rude mailing lists don't invalidate private email conversations. Also, conference calls are a thing.
Anyway, analogies are imperfect, please look in the direction where I am gesturing, not at my exact words.
The point here (and of the entire conversation) is that you shouldn't judge a medium by its worst imaginable actors as long as you're given the right tools that allow you to use that medium undisturbed, effectively putting them into a different silo.
Today twitter allows a very crude, imperfect approximation of this by following people that post decent content and setting the homepage to "latest posts" instead of "top tweets". Ideally we'd have better tools than that.
But the thing is, there's no "outrage Twitter" that's distinct from "calm Twitter." There's just Twitter. Since the value of a social network is in its population, the natural inclination will be towards a reduction of networks, not a proliferation of them.
That is the wrong view on a global communication platform. It's like saying "a certain tone sets the mood for the entire telephone system".
These things should be seen more as silos, subcultures or whatever.
Unless you expose yourself to the firehose of globally popular content.