If draft mode were implemented, I wonder if instead of locking out new submissions it could hold them all in draft mode for 24 hours (or less). Of course, that just results in a flood when the event is over, and again, could discourage users hoping for a rapid ID (plus, how do you distinguish between draft mode for the event and someone who was actively making a choice to use draft mode?), so it isn’t really an improvement.
Again, just spitballing on how it could be done, not whether or not it should be done.