I am not usually a terribly big fan of Simon, but I should probably get over that, as my wife says I am a lot like him…not sure how to feel about that.
But Simon clearly resonates with people in his approach to what he does. I think that all of the reasons that you list are important ones, but one of the factors of his success that we often overlook is the team he is a part of. Whether we like the other judges or not, Simon stands out in the way that he does because the the other judges are not like him. If all the judges were very similar to Simon in his approach, we would find less value in it. In fact if all of the judges were like Simon, I think the show would probably be miserable. I think that part of the reason the show works is that you have a balanced cast of characters for judges.
Simon does certainly stand out from the others and part of that is about him and part of that is about who he works with and I think that the very same thing is true at work. A big component in our evaluation and translation of the behavior of others is who they are around and with…and we have a hard time factoring that in and even recognizing it. I think there is a real leap from identifying a talented individual to building a talented team. We have a very real tendency to say “Simon is very good at what he does, go find me more Simons”, but each additional Simon adds less actual value and you are probably more likely to end up with dysfunction.
I do think one of the really valuable (and rare) things that Simon does is he is consistently straight forward and honest…he does not beat around the bush, and that is something we could all use a bit more of.