Hi
I tend to think it's not the playing skills that people lack ( for style creation), and that it's maybe it's more to do with how to go about it. Manuals are not very clear. Unfortunately a certain amount of initial studying of the manual does have to be done when recording or even editing, ie to work out what notes are allowable, what chord type should be used, figuring out setting of note transposition tables etc. Can be confusing if using a different brand of keyboard. A guitar phrase recorded for a psr wouldn't wouldn't work with a Ketron style, but could be used in a Korg style.

If some of this stuff is not correct, the style is never going to sound right no matter how well a style phrase was recorded.

Over at Korg, there's a number of users that create their own styles using various methods.

best wishes
Rikki