"Others do it too" is not a good justification of course. But his comment also fails to to explain how Microsoft is somehow more evil than the industry standard.
Bootloader lockdown was practically unheard of for the PC/laptop form factor before Microsoft started doing it for ARM laptops. And and it's not even really standard for phones. Plenty of Android phones have unlockable bootloaders (see LineageOS).
I don't think whether one is more evil than Apple/iOS in this regard is a good benchmark.