It's for that last 5% in tone that makes the difference between a good and a great bass. I'm old enough to remember when vintage Fenders and Gibsons were not particularly desirable except for the quality of Pre-70's versus then-current or recent vintage models. Then, some people started discovering that the instruments that were made well enough to have lasted 20 or 30 years also sounded superior. Also about that time Alembic, who had been around awhile, really took off in popularity because as amps of poorer and poorer quality became the norm, onboard active tonal shaping became almost a necessity.
So on one front, there were the copyists trying to replicate the close tolerances, neck shapes and finish compositions of the coveted vintage instruments, and on the other, active circuits went crazy. Sometimes the two overlapped, and in general, the market has not been kind to innovation past accepted "norm;" see Steinberger and Kubiki for examples of that. Since the market and tonal preferences dictate a fairly narrow spectrum of "popular," most upmarket innovation has gone into refining, rather than redefining, the state of the art. US makers are definitely far more conservative than their foreign (Dingwall is Canadian- so not just European) counterparts, probably as a reflection of our relative social/cultural conservatism.
