I got a few thoughts....
Regarding the legal underpinnings for deletion
For reference, here's the current template for "self-destruction of useful content":
You have recently removed or defaced a lot of content from your posts. Please note that once you post a question or answer to this site, those posts become part of the collective efforts of others who have also contributed to that content. Posts that are potentially useful to others should not be removed except under extraordinary circumstances. Even if the post is no longer useful to the original author, that information is still beneficial to others who may run into similar problems in the future - this is the underlying philosophy of Stack Exchange.
Extensive deletions take a lot of effort to repair. I have placed your account on hold for {suspensionDurationDays} days while I reach out to you to avoid any further misunderstandings. Once this matter has been resolved, your reputation score will be restored and your account will resume as normal.
Please respond to this message. I sincerely hope this is just a misunderstanding, but if you feel you have an exceptional reason to remove this content then let me know. If you'd prefer, you can contact Stack Exchange directly through the 'contact us' link at the bottom of the site.
Note that the first paragraph focuses heavily on why we might try to stop folks from deleting their posts. I like this strategy - it cuts straight to the point, which is that we're reaching out because these deletions may be hurting others; critically, we're not contacting them because we wanna debate the legality of their deletions, or because authors cannot as a rule delete stuff - this is objectively false, given authors are the primary deletionists and we generally don't care. In short, the ToS serves the goals already stated in the message, not vice-versa.
I'm not entirely convinced that bringing the ToS or license into this is gonna placate the folks who really want their stuff deleted in the first place... But if we were to do so, we should try & figure out how to work it in such that it reinforces the existing message.
Regarding disassociation
A bit of background: the method for doing this is one of a class of ancient tools that tend to cause more problems than they solve if used regularly - it is second cousin to the old revision destruction tool we used prior to the introduction of the current redaction tooling, if you can recall the headaches that regularly arose with that. Now, we're obligated to remove folks' names from their posts if we're publishing those posts and they ask us not to name them... This doesn't necessarily mean "disassociate" though. The most expedient way to handle these requests is to just delete the post - so we'll generally disassociate only if the post is gonna remain visible on the site and is thus of sufficient utility to warrant the extra effort needed to scrub the associations.
Why do I mention this? Because if you're even using this template, there's a pretty good chance someone isn't just deleting one post - they're either deleting multiple posts, or getting into some sort of battle over a single post. Disassociation might be applicable in some of these cases, but it's just as likely that they want the posts redacted, completely misunderstand how these sites work, or... are just trying to be jackasses.
IOW, we shouldn't presume to know ahead of time what the author's motivations are - hence the last set of changes made to this message to focus on asking for a response.
