Why would an NPB team post its best players now?

If the going rate for someone like Yusei Kikuchi, one of the best pitchers in Japan, is only just over $10 million, how long before NPB clubs see the value in just keeping their top talent until their contracts run out?

Kikuchi's posting shows the MLB-inspired revision of the system will cost Japanese teams going forward and that NPB, and its players, should take notice.