Eh, the cheapest M1 Mac is the Mac Mini at $699, $100 less than the outgoing model and offering better perfromance at some tasks than the iMac Pro. Keep in mind that there is the whole 'profit margin' factor. At $699, the mac mini offers much better perfromance than the outgoing model while costing $100 less. Why chop even more money off it?

Apple's cost in manufacturing has always been rooted in quality components and Software Engineering. They just don't build low end models and likely never will. The fact that you can buy a $300 iPad is actually kinda weird for Apple.

They are probably binning a lot of product right now. They'll eventually need to do something with all those chips that didn't make the cut. This is apple we're talking about. There's surely a 5+ year plan to develop this ecosystem fully. I'd be more surprised if we didn't see a complete line of custom chips across all apple products within the decade.

Isn't latest generation is $100 cheaper and apple usually cheaper than windows-based.