What is the difference between the two? What kind of social media business is there other than selling ads?
It would have the side effect of making the whole business less ghoulish and manipulative, since the operators wouldn't be incentivized to maximize eyeball hours.
It's impossible to imagine this because government regulation is so completely corrupted that a decades-long anticompetitive dumping scheme is allowed to occur without the slightest pushback.
Of course perhaps it’s a bit different now since most people consume content from a small set of sources, making social media largely the same as traditional media. But then traditional media also has trouble with being supported by subscriptions.
The bigger problem is the monopoly. They would charge $4/mo. Then add ads on top. Then up it to $5/mo. Then..
Scaling is harder. But you can have a niche which works fine.