Why is kernel.org doing this for essentially static content? Cache control headers and ETAGS should solve this. Also, the Linux kernel has solved the C10K problem.
The contents in question are statically generated, 1-3 KB HTML files. Hosting a single image would be the equivalent of cold serving 100s of requests.
Putting up a scraper shield seems like it's more of a political statement than a solution to a real technical problem. It's also antithetical to open collaboration and an open internet of which Linux is a product.
A great option for most people, and indeed Anubis' README recommends using Cloudflare if possible. However, not everyone can use a paid CDN. Some people can't pay because their payment methods aren't accepted. Some people need to serve content or to countries which a major CDN can't for legal and compliance reasons. Some organizations need their own independent infrastructure to serve their organizational misson.
Ah true, I think I might have forgotten the context. They're big enough to do that. Most people I see recommending a CDN are freeloading on some big corp's systems
