What we've lost is independent media having outlets to reach an audience. Pre proliferation of centralized social media platforms, it was easier to find independent voices on the internet through more de-centralized means. I remember coming across the works of Fredrich Hayek and Paul Krugman via the same message board in the early 2000s. Diversity of thought was at least respected, even if it got heated.
I've noticed a steady decline in diversity of thought co-existing on the internet as general social media coalesced around Meta (Facebook, Instagram), Snapchat, Twitter and TikTok. Reddit has also had a slower but meaningful decline in the co-mingling of ideas on merits, and perhaps subjectively, I feel it took longer to get there but ultimately has ended up in the same place, an echo chamber.
There was a time I remember, when progressive, liberal, and conservative people also could seem to agree on some baselines, like not enabling racists.