I’m getting annoyed with people that ask a question, have the community answer their question and troubleshoot over several days, only to delete their post and the solution.
The person asking the question is often providing the least amount of effort, so why should they have exclusive right to delete the contributions of others?
Possible fix: have a per-community option to only request deletion.
Any part of such contract that implies giving up rights is void and cannot apply
If that was true open source software would not exist
You have no rights on someone elses property by default. Licenses grant under a specific scope, they don’t actually forbid
The point is that once you have released something under an open license, it’s permanently under that license and you no longer have the right to demand that other people stop publishing it (which admittedly you do have by default). Giving up rights is a thing.
A thing that doesn’t apply here
Can you elaborate? To me it really seems like it does apply. A more related example might be Wikipedia, which has open licensed content. Or even the whole concept of writing for pay with a contract; the person who pays you gets the rights, because you agreed to that, and you can’t just demand they delete it later. These things are within how the law works. Why wouldn’t it also be within how the law works to have a social media website where the condition of posting is granting a non-revocable right to publish what you wrote?
I’m not a lawyer, but in at least the US, that would make sites publishers. They’re not. They’re basically hosts, which, as I understand it, they would otherwise be legally responsible for the content that users post on their sites. No company wants that, but will at least try some form of rules and/or moderation so as to have a defense of good wiill, should they ever have to appear in court due to content users posted on their site.
Edit: clarification
As I understand it the distinction between a website hosting user content and another publisher is Section 230, but that is about limiting liability for publishing user content, and I see no reason to believe that this law would prohibit users from granting such websites non-revocable rights to publish their writing.