Went back a few pages, wanted to note again that "skilled play" and "player skill" are, in this context, very different.
I think in an earlier set of comments I misused these to some degree. When I see "player skill" emphasized as per the OP/title, it's generally talking about "using your skills and knowledge as a player instead of relying on your character sheet/abilities to solve problems." To quote from the Shadowdark GM's Guide to provide a brief example:
"CHARACTER SKILL VS. PLAYER SKILL
Characters aren't the only ones who level up. Players also gain experience!
For example, players will learn where to look for secret doors and what the "tells" are. As they go on more adventures, they become better at gameplay.
Encourage this by giving players the opportunity to make decisions that rely on their creativity and wits, not on their dice rolls or stat bonuses."
There are many games for which that sort of "player skill" is deemphasized, and I'm personally content with leaving it primarily in the OSR definition to avoid confusion.
When I see "skilled play" emphasized that's
generally at least for me referring to
being good at a specific system of play. By
system I mean "this game, with these people, at this table, with these priorities." For the game of 5e one of my players is in, this means being a high charop player who is building to maximize tactical combat outcomes. For the players of my Sunday night Stonetop, that means thinking deeply about character priorities and how to balance those with the pressures of the setting and premise, while making space for deeply felt emotional connections.
A key component of a "skill" is that you don't start out being good at whatever it is. Since I almost never play repeat games with the same group, that means that we start out in a series of slow developments as we all feel each other out, let the group norms shape out, comprehend the system together, and eventually settle into a rhythm of skilled play for our priorities. Very much follows in the vein of Tuckman's stages of group development!
I think that
@loverdrive 's note about a specific GM can be extended to that specific group - I'm the same GM running the same game (Stonetop) for two different groups, yet the priorities of play differ between the two even within the confines of the same premise and ruleset and thus the skills of play we've developed to create the desired ongoing outcomes are different between the two (and I need to display different skills in what I say and elicit between the two tables!).