To me it seems like fighting teen pregnancy by preaching abstinence. We should be teaching a higher baseline of computer literacy, and providing more secure systems that keep the user in control and in the know when it comes to their own device and the software running on it.
Attacking the problem by reducing user freedoms and increasingly monopolistic control is not the answer, even though Google's PR department would tell you otherwise.
As far as I know the reason you don't preach abstinence, beyond enforcing your morals, is that it is not effective.
So the question on if this effectively reduce scams is the first question to answer.
Cloudflare only needs to exist because the server doesn't get paid when a user or bot requests resources. Advertising only needs to exist because the publisher doesn't get paid when a user or bot requests resources.
And the thing is... people already pay for internet. They pay their ISP. So people are perfectly happy to pay for resources that they consume on the Internet, and they already have an infrastructure for doing so.
I feel like the answer is that all web requests should come with a price tag, and the ISP that is delivering the data is responsible for paying that price tag and then charging the downstream user.
It's also easy to ratelimit. The ISP will just count the price tag as 'bytes'. So your price could be 100 MB or whatever (independent of how large the response is), and if your internet is 100 mbps, the ISP will stall out the request for 8 seconds, and then make it. If the user aborts the request before the page loads, the ISP won't send the request to the server and no resources are consumed.