I think that's a convenient marketing justification for the fact that they can't get better silicon. There's every reason in the world to make the M1 look obsolete if you can, but the bum-rush for TSMC's 4nm process may have locked that option out.

In time we'll see if there are greater improvements coming. Something tells me that we're never going to see a performance leap comparable to the 10nm -> 5nm one, though.

It's not a marketing justification. It's the product strategy that underpins the iPhone/iPads growth.

The whole approach centres around consumers feeling like if they do purchase a cheaper M1 model that it is a great, future-proof device and not an obsolete one.

Right, and how did they take that into account when they lambasted the Cronenberg i9 Macbooks for the sake of selling M1s?

To Apple, marketing and product strategy are deeply synergistic. It is for every company at their scale, and especially when you have to sell something direct-to-consumer.

They didn't. Everyone knew that i9 were garbage.

And the only people buying them were those that needed Intel apps that weren't yet optimised for M1.