Here is the full text of the publication to which you refer, as well as the direct link to it:
Cloudflare now defaults to RFC-compliant cache behavior
Fri, November 22, 2019
‘Origin cache-control’ is the cache-control header sent from the origin server that tells Cloudflare what assets to cache. Previously, a page-rule was made available for customers to enable advanced cache control directives from the origin server.
We are now making this the default behavior of the cache to be compliant with RFC7234.
Note that Cloudflare always respects origin-server cache-control headers, unless explicitly overridden. This change should not result in additional content getting cached. You must still set a “Cache Everything” rule for Cloudflare to treat all types of files as cacheable.
As I understand it, unless there is another Page Rule capable of acting on assets in order to override the new default cache behavior, it is no longer necessary to make use of the Origin Cache Control setting in your Page Rules to comply with RFC7234.
You may also notice that the description of the Origin Cache Control setting has been updated on the Page Rules Tutorial to reflect the new default behavior of the cache:
Old description
Turn on or off to apply caching rules with stronger RFC compliance.
New description
Origin Cache Control is enabled by default for Free, Pro, and Business domains and disabled by default for Enterprise domains.
If you would like to go deeper into Origin Cache Control, this article from the Support Center specifically addresses this subject and is full of concepts, references and examples:
