Backups could also protect against someone actively deleting.

Sure but anyone with read/write access, editing/rendering access requirements, etc. is going to have a lot of permissions in most operations. Most editors (and many above the line) can access, move, delete, etc. footage and cuts. Locking them out of that is tricky if you want them to do their jobs. Doing screeners and alt versions would be a nightmare.

People lose footage but this is a bit odd for a major operation. Again incompetence is real and it’s a reasonable explanation as well. It’s just surprising