Comment by hackyhacky

> The echo chamber bubble on the other hand, seems quite unique.

More specifically: using "engagement" as the metric to optimize.

Users' use of content is measured: how long do they watch it? Do they leave a comment? Do they give a "like"? Based on that, the algorithm finds similar content that will elicit an even stronger response.

Every action you take on modern social media is giving information to your drug dealer so they can make the next hit even better. But not better for you; better for the social media, who make money from ads.

The continuously adaptive nature of the input stream as a basis for keeping users' eyeballs leashed to ads is what separates FB, Tiktok, Instagram, and Youtube from the more benign, but still addictive alternatives (HN, Fortnite, WoW, NFL, Reddit).