When learning to program, you end up in arcane states. When learning languages, you end up in arcane states. Even when learning how to drive, I ended up in arcane states.
Obviously a bit of hyperbole, but when hopefully when you learn it and end up in weird states, you have a companion helping you to correct course.
From my experience as sysadmin the people having problem with it also highly correlate with people that just chmod 777 on server if something doesn't work and they don't understand why...
What's worse, is that a lot of people who seem to be asking for the same workflows actually have slightly (or significantly!) different conceptual models of what they want, so we end up in this weird place where we think we all want the same thing but actually don't.
If anything, git has clearly demonstrated that this is a complex space, and its perceived unusability stems from the fact that the operations it supports simply map onto basic graph operations.
Switching Git to Mercurial, or pretty much any other actual DVCS ain't going to make life of artist or someone tech-clueless any better, because while UI might be improved they still don't know what exactly they are doing or why
The reality is, Git is unintuitive, and makes nearly every common thing the average person wants to do a complete pain in the ass. I understand you (and I) know how to get things done using Git, but as a society and a technically community, we should strive to make things better.