Problems with the use of gm/player skill
Just read It is time to ditch the "good GM" and found the aproach mislead.
While I do agree with most of the ideals aspired to in the post it muddled ideals of play with an analysis of gm skill and fails in the parts where it actually is analytic.
Aproaching the topic of GM or player skill the first problem begins in the attempt to grade or quantify it. What players and GM need to bring to the table for it to be a fun experience are mainly qualities not quantaties.
This is most obvious in the qualities nessecary for any group activity and by far the most important in determening if a group is formed in the first plays and stays together time and location. Both of these are quite binary in their outcomes either their is a common time feaseable for all members of the group or there is not and same for location. Sure the their might be some elasticity to it where an individual that particularly enjoys the specific group might go above what they would usualy be comfortable fitting into their schedule/traveling to but very quickly it gets to the point where no matter how "skilled" the GM and group if the time does not fit there will be no play.
This translates to many of other properties of a potential game. Be it the themes a GM uses in their game, the systems players and gm are interested in, the style of roleplay. These are all qualities and whether or not they match will even when the schedules align be the most important for whether a fun experience is to be had or not.
I will not deny that there are properties which can be quantified like GM and players having aquiered a certain depth of knowledge about a system, a familiarity with certain tropes, experience in certain play patterns etc.
While due to the fact that I have great fun in teaching players certain aspects of play (and from my limited experience this is something that most GMs share) I mostly dont care much how developed certain skills are in players as the process of seing them develop is a great fun in and of itself to me.\ But this is just a preference of mine and those with different preferences for whom the lack of a certain skill is a factor to exclude a player or not play with a certain GM thats that is equally as reasnable and I do not subscribe to the idea of holding up my personal preferences as an ideal to which rpg content should adhere to.
The only cases where this muddling together of a plethora of qualities and quantities into one big gm/player skill makes sense is under narrow expectations of playexperience and the pressure of competition under market conditions. Like exclusive familiarity with 5e, expectations of high fantasy and groupfinding in a large population that has a heavy skew in either gm or player direction.\