My point is that secure boot isn't the only way forward, and depending on your circumstances, a foundation built on something like seL4 could suffice for particular applications. And it doesn't even require a whole new OS or foundation like seL4, even Windows has the right core primitives if they're used in the right way [1]. And that work was from 2005, not 40 years ago, but still long before any of this really became an issue.

[1] https://cacm.acm.org/research/polaris-2/