@scottjenson I don't think you're going to be persuaded away from this view. However, the reply guys exposing you to a paradigm different from your own, holding you to expectations you're unfamiliar with, are exactly what makes it not an echo chamber. If nobody ever bothered you or came into your notifs to disagree with you, you'd be in an echo chamber. Which it seems is what you're used to.
In most social media, there might be Nazis and communists on the same website. The algorithm constructs separate "bars" for them by simply not showing them each others' posts, heavily auto-moderating what language you can use in your posts, and recommending you people to follow that you like to interact with because you agree with them.
That is what builds social media platform retention. Mastodon has none of that. Instead, you defederate the Nazi bar and only talk to the bars that don't allow Nazis. Most people don't "get" that because it's always been done for them. And that's OK.