Heard you and that wouldn’t fly. Just like you’re not supposed to run Windows on mission critical systems like nuclear reactors (seriously, check the EULA), running multiple operating systems side by side is most likely out of a supported configuration and “use at your own risk”. You’d have zero standing or less for any sort of lawsuit.
But just because it is in the EULA doesn't make it legal. At a time where big tech is being kept under a microscope for antitrust regulation, I'd say that an OS that actively destroys other competing OSes on the machine it is installed on should be considered an unfair anti-competitor tactic.
Might not hold up legally, but it's still insane that the single largest vendor of operating systems cant figure out how to install a bootloader with playing russian roulette.