Atari, Commodore, Digital, Digital Research, were lacking the management talent.
They had the nicest gear, but the suits botched it primetime. That's why I drink.
Now, more to the point of the parent: Sun and SGI had the management talent. They had a good run. But that run ended anyway. At some point they run out of ideas to compete with "industry standard" hardware.
So, to come to the point of the parent: would a very successful Atari UNIX station, based on the 68030 made a difference?
NeXT used the 68k processors as well. And Apple. Even with the Mac's success the PowerPC eventually run out of steam against Intel. Would an additional load of many, many Ataris made a difference here?
What did ARM do differently than all of those mentioned above?