In this one, Craig Federighi says “We’re not direct booting an alternate operating system. Purely virtualization is the route. These hypervisors can be very efficient, so the need to direct boot shouldn’t really be the concern.”
Allowing booting other OSs is different than actually supporting those efforts with documentation for example. The problem with Intel Macs is not being able to boot another kernel it's all the device support that's now gone.
The fully documented BootPolicy system, all new to M1 Macs and not found on iOS devices, explicitly supports running your own kernel on these devices. It’s also supported by new tools for implementing boot code. Apple has clearly devoted a lot of resources to this, as the Asahi Linux team have repeatedly pointed out.
If your comparison is iOS devices then sure, being allowed to boot your own kernel is a sign of progress. It's a very low bar even when compared to Intel Macs though, not to mention competing laptops. But this is definitely going much better than I anticipated. They've gotten quite far in not too much time. I'm definitely hopeful Apple laptops will again become an interesting option.
Craig Federighi (their SVP of software) mentioned that support for other OSs is an explicit goal of their boot setup in interviews.