As we all know the battle of the processors was won by the Intel x86 series on the CISC side and various flavours of ARMs on the RISC side. Motorola's 68K chip was pretty much doomed to obscurity once Apple dropped it in favour of PPCs (which they later dropped in favour of x86s) and Atari and Commodore went out of business. Likewise Apple's decision to drop the PPC has lead to its demise as a serious contender in the market now dominated by ARM.
So. What would it take for both to be still competitive with Intel and ARM's offerings? Or even dominant.
The 68000 series was MUCH better than Intel's x86 set. It had full 32 bit capabilities much earlier, and a much more logical orthogonal instruction set.
Intel's kludge offset addressing of memory (nothing could be accessed in larger than 64K chunks) was crazy.
I mentioned to a friend once, decades ago, that IBM was brain-dead to go with the 8086. He looked at me oddly and replied that IBM went with the 8086 because the 8087 was a standard, integrated (not integrated on one chip, but integrated in instruction sets, etc, IIRC) numeric coprocessor, and some of their early customers NEEDED math.
So. PoD Motorola decides to make a standard numeric coprocessor to go with the 68000 as a paired set, and IBM goes with Motorola for the IBM PC (and all their clones).
Then, there's no awkward 640K memory limit, we can evolve *DOS to be a real operating system, etc. We might even be able to avoid Microsoft, if we're lucky.
Sound good?