Brian C. Lane wrote:
We have reached a point where boot security is important enough
LOL!
that Windows is now only allowing their bootloader to be used.
It is blatantly obvious that that is actually the goal, not the means.
This is clearly a vendor lock-in "feature", with "security" used as the excuse (just like other similar vendor lock-in "features", e.g., the iOS App Store monopoly).
Incidentally, the "feature" not only prevents chainloading (which can be worked around by using BootNext), but also disabling Restricted Boot ("Secure" Boot) altogether (which is a much worse restriction), because that, too, changes the TPM PCR measurements.
But the marketing as a "security" "feature" clearly works, because there does not seem to be any noticeable public outrage about these absolutely unacceptable monopolistic restrictions.
Kevin Kofler