I'd suggest taking a look at Ferrari's other artwork, he's actually not an unknown and he's certainly on a level that's beyond five years in.
Actually, I boggle at anyone who thinks they're at 'mastery' at just ten thousand hours in. That's the point that you're competent, really. Masters are people who are in it for the long haul, the folks over on ConceptArt clocking in twenty+ years are masters.
Ferrari's other work or what you want to call "mastery" is all irrelevant. manuscreationis said s/he would like to be able to draw as well as what can be seen in this demo. Acquiring that level of skill does not require 10,000+ hours.
Given that you admittedly don't have that level of experience, who are you exactly to decide that again? You haven't even justified that position, you simply state it as fact. If anything, I've found your comments to mostly be "irrelevant".
Working in reduced resolution and color constraints is actually something rather challenging. Lesser artists are going to particularly suffer because they won't have experience to fall back on when they need to find workarounds, especially if their color theory is weak. You aren't going to hit Ferrari's level unless you've already got a solid foundation in place. That's easily five years to be competent at, then you can learn to work within those limitations.
I personally oversee a number of artists around five years in and I wish could get that quality of work out of them consistently.
Why I suggested you see his other work is because I don't think you're actually qualified to assess just how difficult the work is and you should see whose work you're dismissing as amatuer/entry level.
Actually, I boggle at anyone who thinks they're at 'mastery' at just ten thousand hours in. That's the point that you're competent, really. Masters are people who are in it for the long haul, the folks over on ConceptArt clocking in twenty+ years are masters.