Secondly, they're far from ground-breaking. The VAST (Variable Architecture Synthesis Technology) engine that generates their initial sounds was unveiled in 1990 and, despite advances in each of the subsequent generations, it's clearly the same underlying system.
For one thing, they're far from ground-breaking. There's something rather odd about Kurzweils. Kurzweil's latest workstation introduces enhancements - but doesn't mess with that Kurzweil sound.