I'm in favor of letting people pursue their preferences, but echo chambers are antithetical to civil society - much more dangerous than so-called misinformation (indeed, they are environments in which errors and lies are more likely to flourish), so counteracting then is a valuable goal, in my book.
I think you are diametrically mistaken and echo chambers are actually good for civil society because they allow the illusion that people outside your ingroup are basically good. I think what happened is our echo chambers got punctured and so we suddenly got the realization that other people lived in echo chambers, which is why it seems like those suddenly popped up. But well-insulated echo chambers (ie. not what controversy-driven twitter gives you) are good for mental health and society as a whole.
This has some internal logic, but every experience I've had contradicts your proposition.
For example, I'm in my late forties. When I was growing up, it was rare to encounter (out) gay people outside of major cities, and people would believe practically any negative statement about them, not so much anymore. Conversely, in my college town today, most of my accquaintences have never met a Republican, and they predictably believe in a stupid cartoon caricature of red staters. I'm definitely not buying it.
Maybe if you have safe spaces (echo chambers) and overlapping meeting places, but also a strong standard of not policitizing the meeting places, you can get the best of both worlds?
