Let me throw out some metaphorical examples to help express my thoughts:

I love to go bowling, and actually kind of good at it. I have an average of 230, but I only like to bowl with friends despite the fact that I know I am good enough to roll with highly skilled bowlers. I simply choose not to. Meanwhile, my brother loves bowling even more than I do, and plays in a league. He WANTS to bowl with the big'uns, but is having trouble getting his average up.

Can you see where I am going with this?

The way this translates into FFXIV is that player skill cannot be defined by the amount of content they do, the content they participate in, or even the clears they have under their belt. In any content you do, you will indeed experience varying level of skill amongst all the players, and this is one of the reasons why I love and hate roulette. The game does have a basic difficulty tier in the content that is released, and I believe within those tiers you can start to divvy up the skill levels of the players that participate in it.

I am not one to find enjoyment in evaluating player skill. I much rather players strive to be better at their jobs than they were the previous day, regardless of their current skill level.