I am aware of the reasons delete has not been restricted before, but the reasoning has begun to unravel on Stack Overflow, where a fairly large pool of users now have access to that privilege. I give you exhibit A
Yes, we can stop it by locking it (which I did), but locks are a poor tool here because it prevents ALL post interaction (which isn't fair to the user, who is not part of this "meta" argument). Moreover, motivated users will simply out-wait the temporary locks. I had to moderator delete another question to prevent the same problem. Neither solution is great. There's no real policy to quote to people doing this either, but it's becoming a more common problem.
I think the time has come to restrict delete and undelete for regular users (not including the OP) to once per post, just like (successful) closure. It's clear that motivated users with that privilege will continue to delete/undelete ad nauseum, and it actually diminishes the delete privilege because people who disagree will get more votes tomorrow to change it back the way they see fit. Add in Meta effect and it can prevent community consensus, leaving mods to fix it with nuclear weapons. With limited deletes on a given post it forces a detente at some point, and it's a level playing field for all.