Edit: 97% is a real number, not an exaggeration, based on numbers from the report linked in the article.
Edit: 97% is a real number, not an exaggeration, based on numbers from the report linked in the article.
Similarly, if you block cookies/supercookies/etc to avoid being tracked ... you'll be challenged every view.
The need for incentive you mention is silly. The website operator [much like a job searcher with a resume] wants to be in front of as many non-malicious people as possible. And while you might argue .04% of malicious traffic comes over Tor, I've operated sites where 20%+ came over some sort of proxy with poor IP reputation.
You know what?
Fuck it. I'll just build my own site that doesn't use Cloudflare for such a purpose.
It all depends on what you do. I had a customer a few years ago that was forced to geo-block IP addresses from China, most African nations and Bulgaria. The nature of that customer's business made that an easy solution.
A company like Cloudflare serves everyone without a lot of context. If your site serves a Tor-heavy niche, it's not the right solution.
Is there really a constant DDoS attack on all of these sites from users with no cookies?
One could setup an IDENT-like service that delivers a hash for the source's route, and that would enable better scoring, but also could be used as a tracking measure... you can't have one without the other.
Even then, it would take either the user allowing cookies, or the TOR system to change their exit nodes.
Listed those in other responses.