The M1 is the Core Duo
Apparently the "M2" has gone into production, hot off the heels of an ExtremeTech piece about how Apple's M1 Positioning Mocks the Entire x86 Business Model.
It is a curious phenomenon how the M1 is the same chip in the Mac mini, MacBook Air, MacBook Pro 13" and now iMac (save for the binned 7-core GPU). It is curious how the chip can still, to some degree, whip even higher-end models; and it is curious which strategy Apple will use going forward for chip differentiation.
Following the iPhone/Apple Watch model, the idea is basically that all models get the latest chip, and then next year, last year's model slide down. The iPads having more models instead use a wider spread of chips, although all pulling from chips that were once the best.
I can't claim to have a firm grip on the future strategy, but considering both the break from the past, the relative performance but also the architectural bummers, M1 to me looks closest to the first Intel CPU Apple shipped in a product, the original Core Duo codenamed "Yonah". It was the product of Intel's backpedaling from the Pentium 4 Netburst architecture which was the inevitable endgame of always chasing CPU frequency at any cost, it equaled or outdid the Pentium 4 in performance, it ran laps around the G4 and G5, but it was also hopelessly 32-bit.
Yonah was the first shot across the bow as Intel recalibrated, and soon led to the Core 2 (with increasing core counts) and later to the i3, i5, i7 and recently the i9 marques, not to mention bleeding the architecture to the Xeon. It was hard at the time to not be impressed by the Intel Core Duo, but there was also a short while where it was everywhere simply due to being the first chip out of the gates.
I don't think Apple will make more chips than they have to, and I think they're likely to keep up their idea of making a chip "this" powerful, and then building a product around that level of performance, rather than providing tiers of increasing capability. But I also think having the same chip in the Mac mini as in the iMac as in the MacBook Pro 13" is a temporal flub; a child of necessity. What they will do is highly dependent on how often they wish to rev their chips, how big those revisions will be and how likely they are to make customizations. Considering the wide-ranging SoC duties, it already is not likely that the M1 in iMac is the exact same as the M1 in the Mac mini.