The best part of the whole "Jack Tramiel leaves Commodore, buys Atari" story is the part about Atari floating debt to Amiga. The debt was coming due around the time Tramiel bought Atari and, at the last minute, Commodore acquired Amiga and Atari was paid-off. There was litigation following-- Tramiel was never one to let something go quietly-- but in the end we got the Commodore Amiga.
In some alternate universe there were Atari Amigas and likely no Atari ST.
My understanding is that Commodore had a Z8000 machine in development. It would have been neat to see what they came up with, in light of the fact that Shiraz Shivji went to Tramel Tech / Atari. All silly speculation, but it is so neat that, effectively, two major players in a market “swapped” their engineering staff. Surely that’s an odd scenario.
In some alternate universe there were Atari Amigas and likely no Atari ST.