I repeat, it has never been necessary to re-take any part of the [PPL] skill test in order to maintain (or regain) the currency of a PPL.
So you wouldn't expect a proficiency check to include stalls, steep turns, PFL, EFATO, different landing configurations/approaches? They are in a proficiency check and "part of the skill test" - so technically your statement is incorrect, if we're going to be pedantic about individual words
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You can fail a proficiency check, so it is a test in effect. Which is why I can understand why some people may call it a skills test in error - rather than castigate them for it. I think everyone here understood what was meant by the OP's question, but only some decided to provide a helpful response.