[Dumbdo]

I assume they do that do avoid comments on old issues. If they are already using bots like that they are probably barely able to respond to new issues, so comments on old issues will never be read anyways. By forcing users to open new issues, it increases the chance for replies.

That's at least what I understood from bigger repositories. It's not great and most maintainers are aware of the several shortcomings of that practive, but especially in huge repositories there are so many new (and sometimes low effort) issues daily that some maintainers are simply overwhelmed.