I think we should recognize the mastermind of Gary Willis who invented the finger ramp for his own style and esquisite technique. I used it for fretless playing and it's a real plus.
These days the finger ramp is kind of generic accessoire and it is used in many cases just for the hype.
The funny (or sad) thing is that this ramp (which is a little piece of wood between pickups or betweem central pickup and the neck) is proposed by a NY bass company, at only 399$ !!! - They really think bass players are stupid...

Best regards