I'm not sure I get your point Amiga nut, either the management was or they weren't at fault.
And personally, I always tend to think of Amiga and the rest of Commodore's line separately (although, God knows, management didn't make to many great decisions developing the Amiga line either).
Frankly, I think they just got too used to the high profits generated by $200 C64s that had a $2 processor in them and they couldn't get it past their thick heads that that situation couldn't last forever.
And I wish I could have been a fly on the wall during the C128's design sessions. I want to know which genius went "I've got it, we'll make it capable of running CP/M 'cause God knows those C64 users love programs without graphics and sound".