If you make the price high enough sure, but I'm unsure you can find the right price to simultaneously 1) deter bot traffic and 2) be appealing to actual users.
the individual user is now priced out and cannot speak candidly and anonymously, while large, wealthy orgs simply price that into their market-capture and consensus-building techniques
Dead internet is the prequel to dead world, let's seize the opportunity to learn how to coexist with synthetics and develop the code that will make life with a higher intelligence species possible on Earth. And remember, we humans vary widely, and just like there are people happy to share LinkedIn slop today, there will be humans gladly living surrounded exclusively by overpowering synthetics. So lower your expectations for universal solutions and focus on niche.