Cache: directive is very useful for many circumstances, especially for information archiving purpose, what a shame Google even want to cancel it.
Any archival purposes should use the Internet Archive; Google's cache couldn't be counted on to remain present and unchanged, even before this. (The Internet Archive can't be counted on to remain unchanged either, but at least the Internet Archive will either remain unchanged or disappear, never change. I wish archive.org didn't auto-nuke entire sites based on robots.txt, because when domains disappear the domain squ…
https://blog.archive.org/2017/04/17/robots-txt-meant-for-sea...>
https://blog.archive.org/2016/12/17/robots-txt-gov-mil-websi...>