> Amplification means getting content in front of new eyeballs that wouldn't have otherwise seen it.
Which a CDN does as well. If a user visits the site during peak demand and the site without a CDN can't handle it, the user doesn't get the site in front of their eyeballs. With a CDN, they might. Analogy also works during DDoS attacks. Both assume that the user doesn't have infinite memory and patience to keep trying (because that's a realistic assumption).
"Amplification" has be overloaded. You are talking about a viral marketing definition, whereas CDNs are a hardware+software force multiplier for performance.
Cloudflare can't block access to a website. They can protect their customers from DDOS attacks, and they happen to do it more cheaply and effectively than one could do alone. If they refuse to service a website and that website gets DDOSed off the internet, that is not cloudflare's fault.
Access means people who WANT this content can get it easily. If you're making it harder for people who voluntarily choose to view 8chan content, you're restricting access.
Amplification means getting content in front of new eyeballs that wouldn't have otherwise seen it. E.g. if Facebook determined that given this user's age, race, zip-code, and favorite TV shows they might be in interested in this racist-meme sharing group that one of their friends joined, and then surfaces that content, that's amplification.