With consensus comes trust. And it was trust in institutions — government, media, and religion — that buoyed the 20th-century glory days Sasse hearkens back to.
Trusting politicians and profit-driven media has always been naive. The most salient difference between now and the supposed 20th century glory days of my grandparents and the Cold War is that corporations (and wealthy individuals) used to pay their fair share of taxes.
Corporations pushed changes through over the course of years by way of influence and lobbying, demonstrating precisely that these institutions never should have been trusted in the first place.
More speech chambers is probably a band aid on bigger social woes that underlie people feeling like they need to say a bunch of objectionable nonsense. You can look to British and European parliamentary models and then look to their streets and see that the more speech chambers models don’t really have a drastically different result. You still have Brexit as a dividing line between racist nationalists and everyone else, you still have neo-Nazis rallying in the streets in Germany, and Islamophobia is rampant across the entire continent.
In reality, there is probably no way to reconcile representative democracy and capitalism. If those remain in place, no amount of speech chambers are going to provide legitimate, actionable solutions to our problems, some of which, such as an impending climate apocalypse, are quite daunting