I scored an F in my GSCE maths, if I can understand it and use it, so can they, I suppose if you want to understand the whole code behind it that would be impossible for a normal person including but honestly I think they're exaggerating if they consider the idea of difficulty and mining blocks to be hard to understand. I know the basic theory behind Bitcoin and I know it's open source, that's all I needed in order to make the decision to trust it, some people just clearly either need to do their research or grow a brain.

Basically, this article seems to be a different spin on the same bullshit we've heard since Bitcoin's inception, they'll be saying this crap when it hits $1000 again.