That will give them loads of data to smooth out the kinks out of Rosetta and the rest of software chain while having enough time to work on the M2.
I expect the first "real" Apple silicon hardware will be in November 2021 staring iMac and MBP 16.
Then 2022/2023 for the MacPro where Apple really goes all out, deprecate the last of their x86 line up but at this stage we are at the M4 and nobody cares anymore.
Wish Apple would reintroduce those with the M1. Awesome form factor, held back by Intel's anemic Core M CPUs.
But yeah, I agree they must have a roadmap past these limitations. When we get a 16” MBP I’d bet on it having more RAM and 4 thunderbolt ports. They’ve launched the low end machines with M1 first because this is a first step in the M-processors, and it’s the first time they’ve had any sort of thunderbolt controller with this architecture.
Makes me wonder if any of these changes will make their way back to the iPad Pro. Right now they’re USB-C without thunderbolt, but the new iPad Air is getting awfully close to the iPad Pro’s territory. Thunderbolt support and being able to drive a 6K display would be an interesting differentiator.