No C= & no Trammel probably means no 16bit Atari either...
(C= wouldn't have been round for long without the Amiga & Atari's 16bit platform was down to JT)
...I guess even greater dominance for the PC
Maybe Macs would have a larger market share too...
...Maybe some of the 'local' platforms would have been more viable for longer..?
Regardless, it would have made little difference to me being being late to AmigaOS - my 'first Amiga' was a copy of Amithlon.
I'd been using Acorns of one sort or another & still do.
I suspect in the UK the Archie would have been more main-stream without C= (or Atari) for competition & would now be more than a niche platform.