Yeah, difficulty with medium really depends on the person. Back when I used to do digital I was actually more lazy with it than my traditional, but the process was less enjoyable so I didn't care about taking my time. Also there was no fear of messing up so I had a big "fuck it!" mentality, and the finished product never felt satisfying. Ctrl-Z also made things twice as fast for me, even now when I doing touch ups I smack those keys for a quick fix. (Hell I use that key combo for everything)
Ironically though, digital took about the same time, if not longer than my traditional drawings. But that was more due to frustration with how the tablet pen translated, and the over abundance of colour and program materials.
I can see how traditional work would be more of a challenge for some (able-bodied peeps) who've grown up on digital, but it also depends on how you go about it. Slapping a generic head-shot on a piece of paper with little effort isn't very challenging compared to a full background illustration, a full-body shot with dynamic posing, or even a head-shot done in a complicated style like Mucha's or Dali's works. And stuff like that can be challenging regardless of medium.
