There are plenty of public interest limitations on free speech. Food labels, cigarette warnings, deceptive ad laws. Regulating addictive social media isn't really an outlier here.
The issue isn’t with reading or consuming content, as was set up in the challenge above.
The issue is with designing feeds and surfacing content in ways that take advantage of our brains.
As an analogy, loot boxes in video games, and slot machines come to mind. Both are designed to leverage behavioral psychology, and this design choice directly results in compulsive behavior amongst users.