You can bet that Yamaha is not going to change the key size on their arrangers any time soon. They've been doing it that way for many years, and the uproar isn't nearly loud enough. Maybe it's because Japanese people as a rule are smaller!
Be aware also that Yamaha starts hyping new keyboards usually a full year ahead of their availability. One exception was the 2100, but it wasn't really new, but a makeover of the 2000.
DonM