My point is that if Apple didn't need more time on a proper Apple Silicon-based successor to the Intel 27" iMac, they wouldn't have updated it. They didn't update the Intel 21.5" iMac (when they just as easily could have) which only further lends credibility to the rumors that an Apple Silicon 24" iMac is imminently ready to replace it.
I suspect the new entry level AS iMac is indeed ready to go and that's why the 21.5" got left alone, Apple probably wants to launch this model in time for xmas if at all possible.
I think they launched the 27" because it was probably in production (or close enough that they had the parts lining up in the factories) so it made no sense not to release it. They would have likely been developing Intel and AS macs in parallel waiting until the AS was ready to hit the launch button.
I read a very interesting article talking about Apple shifting focus from hardware to services. Their services revenue has grown very strongly in recent years and is now a very significant proportion of their revenue. The author attributed this shift to the reason Apple launched the iPhone SE at such a surprisingly low price point, they are looking to get users onto their services and are willing to sacrifice hardware margins in order to do this. Apparently there is also a rumour of a $569 iPhone 12 which again, is substantially cheaper than most would have predicted.
He goes on to point out that Apple is manoeuvring to branch into enterprise services with the acquisition of companies like Fleetsmith. If this guy is right, we might see that $800 MacBook after all.