How do we even define 'high skilled' and 'low skilled.' If we're thinking about the group finder for content like mythic dungeons or raiding there are basically two metrics that 'the community' uses to define you as one or the other. Item level and achievements. Now, obviously this has it's flaws. It's pretty cheap for example to get a boost for heroic archi - in fact in the EU you could buy and sell a game time token on ah and have change left over after your boost. Item level is a bit trickier to cheese but at the end of the day for everything but the most difficult content pvp gear is more than good enough - and much more time convenient to get.
Even using these metrics pugs more often than not fail anyway in trickier content but there are a few areas where it becomes annoying. Example: friend of mine recently returned to wow and cannot get in mythic dungeon pug groups. Why? Item level is too low (he's at about 695 or something so clearly not) This person raided end game content from TBC until MoP and is absolutely far more 'skilled' than most of the WoW population.
In conclusion all us wow nerds (lacking the social skills of normal people) basically judge people by a number or their ability to link an 'achievement' they very well may have bought. And then we have the nerve to describe this as being high skilled haha!