Right, and to some people of a certain temperament, being aware of, and concerned about a vast range of entirely different issues, all of which can be engaged with on a number of levels that build on your knowledge and understanding, all of that is just an "echo chamber".

The echo chamber argument doesn't account for the fact that people can have shared fundamental values and nevertheless have constructive valuable informative conversations that engage in nuanced analysis. Being concerned about climate change, for instance, you can have all kinds of productive conversations about new research showing how hot September was, or how to make cities more walkable, or any number of things, and those are valuable conversations where describing them as echo chambers is silly. They're actually good conversations where we gain something from having them. If your primary test of a community is whether it does or doesn't have echo chambers, it doesn't have meaningful things to say about cases like this.