But isn't it dangerous? How does it know you re not preloading the "please delete everything" link?
It would be nice to have a standard html tag preloading="yes" so that one day browsers can have it as standard feature. I'd much rather have this than AMP
In a perfect world no-one would be using links for actions which modify state - they should always be a POST behind a button, not a GET behind a link.
But in the real world this is probably a legitimate concern. They do have methods to mark links as non-preloadable (https://instant.page/blacklist), but anyone using it should definitely do a thorough test, not just copy and paste and hope for the best
As a sibling comment points out, if it's possible for someone to delete everything via a link, your users have already lost. Someone could, e.g., trick your users into loading an IMG tag or an IFRAME pointing to that page, or give them a shortened URL that redirects to your "delete everything" page.
GET requests should never have side effects.