You certainly may _want_ to eliminate such places and/or such beliefs. But stamping out places or beliefs doesn't really work. People find or create new places, and what is left is just ill-will and further political division. Beliefs become martyred and the Streissand effect draws more people in to investigate.

The way to reduce bad beliefs is to, IMHO:

1. Ingratiate and investigate. Respect the people, become their friend, listen to their full arguments (don't imagine straw men), understand their motivations. You might even discover the belief isn't so bad. If you don't, continue on to:

2. Suggest alternate ways of viewing the situation. People will always argue their point and appear to not accept your view. But I've found they almost always actually move slightly towards your point, oftentimes after the conversation, even if they won't admit it. It takes time for a worldview to shift.

Arguing makes no sense prior to ingratiating yourself, because if you are an enemy your view will not be appreciated.

One very important thing to counter hate is to try to have everyone in society involved in society somehow. People are much less willing to wish ill on others in society (or society itself) if they feel that they are part of it. A lot of stories about people being radicalized start with a person feeling at end of the rope and alone.

This isn't something that you can really do online, but it is something that can be done in real life and should probably done more. Friends are a powerful force.

"The child who is not embraced by the village will burn it down to feel its warmth."

This is exactly the way that the broader society changes beliefs on individuals, I think the danger is that individuals can now create their own subcultures which are more significant (to them) than the dominant culture. At some point you don't need to talk to anyone outside of your subculture.

One example is subreddits: over time they start to develop a subculture and the mechanics of downvoting and upvoting means that people with more moderate beliefs can end up leaving after awhile, leaving the subreddit to become more and more polarized over time.

This makes it hard to have these types of empathetic conversations.

People create new spaces, etc, but if you are able prevent the formation of echo chambers that is a victory.