I wouldn't expect another M chip to be groundbreaking in the same way ever again. Instead I just look forward to incremental improvement year after year, the same with the A chips. That's more than enough.
Something similarly groundbreaking would requite a similarly radical redesign. Maybe there will be one another couple decades from now, but I can't even begin to imagine what it would be. Maybe something related to ML if anything.
How well the M series will do over time would be based on its comparative performance. For all the “not that impressive” gains of the M2, there still seem to be plenty of people that historically wouldn’t buy an Apple computer but are ‘begrudgingly’ buying Apple laptops due to M series performance. Have we seen anything that delivers a comparable value proposition, let alone a better one?
It seems natural that M series chips won’t forever be uniquely positioned ahead of the pack. I don’t think that anyone besides Apple actually wants that in the first place though. I have every expectation that they’ll keep up with the pack, or simply move back to third party chips, even if that means changing architectures, which Apple is not scared of doing.
Something similarly groundbreaking would requite a similarly radical redesign. Maybe there will be one another couple decades from now, but I can't even begin to imagine what it would be. Maybe something related to ML if anything.