I don't have data to back this up, but I suspect the main issue with needle skip is from vibrations being transmitted through (and maybe amplified along?) the arm. Since the arm is still mounted to the base, it could be that levitating the platter does zilch for vibrations. I wonder what it would take to levitate the arm too, and just have a flexible cord hanging down to pass along the signal?
Eliminating needle skip was the first thing that came to my mind too, there's gotta be a reason they don't even mention it.
I'll preface this by saying any attention paid to the performance of record players is an absolute waste of effort, in my opinion.... buuuut.
I think that there's a different problem for each component. The turntable introduces vibrations vertically (which seems less important to me, except it could affect stereo), and the arm introduces them horizontally.
Eliminating needle skip was the first thing that came to my mind too, there's gotta be a reason they don't even mention it.