Comment by rincebrain

Evidently you can, though in traditional macOS fashion, you exploit Apple secretly changing the setting for you if you do a magic dance.[1][2]

I've never had a reason to try it, but there's also a remark that 99% of the Macs sold probably don't need to change the system-wide keyboard layout defaults, either...

[1] - https://heylon.ca/how-to-permanently-switch-default-keyboard...

[2] - https://support.apple.com/guide/mac-help/change-the-system-l...