It's not an "echo chamber" if you just don't want to talk to people with polar-opposite views. You're not going to have a productive discussion between, for in

It's not an "echo chamber" if you just don't want to talk to people with polar-opposite views. You're not going to have a productive discussion between, for instance, anyone on the left and a group of neo-Nazis. Excluding neo-Nazis from a discussion doesn't make it an "echo chamber". As for being heard, maybe the problem is no one wants to waste their time and breath dealing with people with such different views. When literal decades have gone by and those people still cling to same views, there really isn't much point in trying to change their minds now.