"If your conjecture is correct, do you think I should reconsider?"
I have no way of knowing whether my conjucture is correct not, but I suspect that it is. Having said that, I will be watching the Oct. 30 event with great interest, and suspect that, should new iMacs be announced, I will probably get one. With reservations. I am 68, and am unwilling to retreat to Windows despite my suspicions of Apple's future plans, because it is the path of least resistance. My current 27" iMac will be 4 years old in December, and it is about time. I will, this time around, go with a SSD rather than Fusion drive, and hope for the best. Still, I am somewhat ambivalent about it due mainly to the fact that Apple's unslakakable, unmitigated naked greed---which is out there for all to see---disgusts me, and I feel conflicted about giving them any more of my money, because it means supporting a company (rather, a lifestyle "Brand") which I feel has become a monster which desperately and cynically attempts to present a human face.
Do what you feel is best and what you are most comfortable with.