I find a lot of the noise in contemporary content is calls to action(payment). Your idea might just ensure content that is mostly about trying to get people to pay for it survives.
What it would do is put a price floor on content. People's willingness to pay, say, $5 instead of $1 for a piece of content is a strong filter, I'm pretty sure low-quality content that's purely CTA wouldn't survive.
Why do you need state enforcement for such a filter? If you only want to see content that the author is asking $5+ for, that's a very simple filter to implement for any website that sells content (and many of them do just that).
The problem is that a lot of potentially viable content falls by default into the marginally-profitable category, where the small amount of utility they provide to the end-user is offset by the incessant user-monetization impulse.
A price floor splits these marginal works into three categories: those that become free, those that die off, those that become viable at high margins. This seems to be a pretty great outcome for consumers.