Except there is more player skill in D&D at least for combat. Move, target, ability selection, coordinating with team mates abilities, etc.
There can be, sure. A heavily optimized high tactics play table is going to look very different then one where people get together to BS and talk at each other most of the time, but I might put that down under "system mastery." When I've seen it in theory-style usage, "Player skill" is usually making a distinction from "character skill" and often with some derision (or at least distinction) about "buttons on character sheets" and the like.
eg:
"
Think Outside the Box
Kindreds and Classes grant a number of special capabilities useful during adventures. However, more often than not, hazards, challenges, and foes cannot be overcome simply by using traits and powers listed on the character sheet. Careful investigation of the environment, creative use of equipment, clever plans, and harebrained schemes can be equally effective. See also Narrative Interaction, p150."
or
"There’s no list of skills or abilities to limit what you can do within the fictional world. Don’t ask “Can I make some sort of test to look for…” or “Can I make a test to disarm…” Instead ask questions like “Is there any tension as I slowly open the door?” or “Do I hear anything if I tap on the wall here?” Interrogate your surroundings by asking questions and state your character’s actions: the GM will tell you if you need to make a test of fate.
and
"
Solve problems orthogonally
You should be trying to make your GM say: “I didn’t even think of that.”
In an RPG, you can do anything. That’s the appeal! When you’re playing a computer game, you can only do the things the game designer programmed in. They anticipated you moving left, right, and down. Going up is out of the question. Not so in a tabletop game.
Most problems aren’t solved by fighting them. People can be reasoned with. Monsters can be placated. Traps can be avoided. Monsters can be led into traps. People can be sold the monster’s guts.
Don’t expect to “use” your talents and motifs to solve a problem. The abilities and items you have listed are just tools—and they’re only one of the many tools in your arsenal. Think outside of your adventurer sheet."
(from Dolmenwood and His Majesty the Worm respectively)