>Sun and many others were betting on 68k, too.

Sun launched its first SPARC-based system more than a year before the NeXT launch in October 1988.

Sun came out of Stanford and was aware of the Stanford and Berkeley RISC architectures (the latter of which led to SPARC). NeXT had academia heritage, too, via Mach from CMU, but I guess it wasn't enough to persuade Jobs to go for a more exotic architecture than the one he was familiar with from Apple, or the "enemy" in Intel.

One can see a world in which NeXT goes with 80386 from the beginning, eventually pivots much earlier to software-only, and becomes a real rival to Microsoft and IBM in the early 1990s to provide a multitasking successor to DOS. Or, for that matter, IBM goes with NeXTSTEP (or just buys NeXT) instead of the AIM Alliance.