Yeah that's nonsense. They already have bootcamp.
That’s incorrect. Bootcamp has not existed for a while now.
Looks like it still exists, they just never ported it to the ARM chips, presumably because nobody wants ARM Windows.
In any case that's really irrelevant to the main point which is that Apple appears to have no objection to other OSes running on their laptops.
Though I wouldn't be surprised if they don't go out of their way to help and make it de facto impossible through secure boot systems.
Why?