Macintosh should have been a stop-gap effort until they could scale production of the hardware LisaOS needed.
Instead of turning the Lisa 2 into a "Macintosh XL", they should have shipped a "macbox" runtime for the LisaOS platform that let it run Mac applications inside the LisaOS runtime.
When they went to 68020 and RAM dropped in price, evolved LisaOS should have been the answer, not System 7.
My view of the history is that Steve wanted to take the Mac simultaneously in two directions: Get the “classic” Mac cheaper and more capable for home users, and build out a “Big Mac” line of workstation/business machines.
Both of these eventually happened despite him getting fired, but the Mac II series was only a workstation in the hardware sense.
IIRC, Steve had negotiated the UNIX license for Apple before he left. Given where NeXT went, I wonder if a Steve-driven “Mac II” would have included the OS rearchitecture that was otherwise delayed a decade by his absence.
I mean A/UX was effectively that, and it's Apple's fault for not properly maturing it into a general purpose product for all Apple customers?
I understand part of the reason was the license cost was so high?
You put your finger on Apple’s big problem in the inter-Steve era: Product.
They had all the pieces, or certainly the smart engineers and designers to build the pieces that were missing, but nobody with a strategic product vision to make the pieces fit.
The most serious indictment of their product thinking or lack thereof: They planned originally to do a total software compatibility break with PowerPC. Power Macs were a success rather than a disaster because a few engineers ran a skunkworks emulation & hardware design effort to build the bridge from 68k.