The active staff is currently 1 admin, 3 mods 2 curators and about half a dozen shadow mods. I don't know exactly what the shadow mods do because none of them have ever actually spoke to me.
So 6 people keeping law and order currently. I guess technically it's my job since I'm an agent of the deep state but I'm also very lazy.
But this isn't anyone's day job so you've got maybe a couple at any given time. There's also a gap during the night where we're all probably asleep at the same time.
But even if you had a mod that was somehow available 24/7 you'd still want several mods anyways just because, and this isn't obvious, we actually discuss potential problems and the actions we take.