I had this idea / pet project once where I did exactly this for email. Emails would immediately bounce with payment link and explanation. If you paid you get credit on a ledger per email address. Only then the mail goes through.
You can also integrate it in clients by adding payment/reward claim headers.
Bill Gates already had this idea. All efforts to change email were already documented 25 years ago. The biggest changes are it is more centralized these days, SPF/DKIM/DMARC, JMAP innovation, oh... and one more thing! It is HUGE!! HTML email is the default...
And it would even still work for the CEO, they would just have to charge more than $1.
The real problem is we don't have a low-friction digital payment system that allows individuals to automate sending payment requests for small amounts of money to each other without requiring everyone to sign up for a merchant account with a financial bureaucracy.
You can also integrate it in clients by adding payment/reward claim headers.