This site is infected with cloudflare, can't see the article.
Servers put the most requested into RAM also.
Not always. Most CDNs for websites (essentially reverse proxies) don't cache pages by default so private content isn't made publicly available. You have to enable/configure what is cached.
In this case, Cloudflare isn't caching the HTML: "cf-cache-status: DYNAMIC". If page cache was enabled, it would be something like "HIT" or "MISS".