I think it also depends on whether or not they were provided the education to use the internet well. If all people get is a vague "have at 'er!", of course we would have more echo chambers. Ever hear the saying "don't believe everything you read online?"

Properly teaching people how to verify their information sources and how to reflect on things would probably result in fewer echo chambers. "Huh. I don't want to keep looking like a fool who spreads obviously false things around."

There's also internal bias to think about here. If someone is already dead-set in believing only their current mindset, they're likely not going to be open to other sources. Instead, they're probably going to search for whatever will back up their claim. People don't usually try to prove themselves wrong in an argument.

This means that part of getting rid of echo chambers will also be teaching people to accept and acknowledge their own errors. We should be teaching people to go for the best answer, not to just prove themselves right. In this way, this problem also preceeds the internet. That mindset has hindered science for literal centuries. It even goes back to the first days of science in Greece. (Thanks for that attempted halt of progress, religion.)

It's easier to blame the internet than the people doing these things. Sadly though, it's in human nature.