So, for projects with 100+ stars, add a wait period of 60 seconds until the delete button can be clicked _after_ the number is typed in. That should allow most users on autopilot to snap out of it, or make drunk users switch to a different tab and forget about it.
"You have 55,231 GitHub stars. Please type 55231 if you want to delete them all."
But I guess, if you delete repos often enough, this will also become muscle memory.
Edit: Just saw the other comment here suggesting the same: https://news.ycombinator.com/item?id=31033996