Because if you do that your bubble will get smaller and smaller.
For some of us, this bubble is the only place their identity isn't under constant attack.
Bigots and liberal ideas exist everywhere. We won't miss anything by excluding them.
Creating a total commie bubble within a liberal society would take so much fucking effort that suggesting that blocking safe havens for bigotry prevents us from seeing important ideas is actually hilarious.
Yes, but as far as I know, it isn't actually deployed anywhere, just researchers testing the viability.