Why do people need so many styles?
To sound as authentic as possible, with a specific songstyle..
And don’t have the capabilities or time to create their own styles.

When can you work with a smaller set of styles?
When you don’t care about authenticy, but are a musician that intends to make his own version of a song..

top keyboards sd90, Genos and pa4x have a whole plethora of tools to create your own styles or edit excisting ones..

The fun thing about todays arrangers is that they fit all these needs..