In my case it's at least triple that, but I haven't really been keeping track of actual time on Steemit. I know when I get on for any given day and when I shut it down in the evening, but the in between will include bathroom breaks, preparing to eat or going to grab something to eat, eating, and miscellaneous things like laundry, taking out the trash, etc.
But 60 hours is a good baseline, and probably goes up from there depending on the day. This week, I'm hoping to have every day through Saturday to devote to this so, the time might be higher.
For me, it's getting the tuning and then the fine tuning down with the curation. That can take plenty of time, I would think. But once you've got the rhythm, then I can see how it wouldn't have to take so many hours a week.
So, I suppose each has its tricks and work to it.