Because of:
- 2000 euro price tag
- no harmonizer
- less expansion options
- no touchscreen
- less real-time parts (no second left voice, no third right voice)
- some features less or modified compared with G70 (eventhough there are many enough that weren't present before)
- keybed of less quality than G70

people will not think of it as the top keyboard.

But Roland clearly stated IT IS the flagship for BK series. I don't think there will be a "topper" offer and I do believe the BK will stay for a while to be the arranger instruments line from Roland.

Maybe a future refreshed G series will come back, but I don't think is for very soon.

And to answer the question - I believe there absolutely nothing wrong with it. I wonder myself how come there's so little noise about it. Or maybe there is enough, but not here.