It seems you are misunderstanding the situation because you are talking about not making “it” an option and you are then reiterating what I also said.
Even if I repeat myself: I think there should be one default formatting that is standardized and there should be the option to emit in other formats such that everyone can read in the individually preferred format.
With fmt you don't need to establish formatting rules on a project basis, anymore. Everybody can just configure their editor to format the code how they want it to look. That is why I think rustfmt should be compilable as a library, too.
Even if I repeat myself: I think there should be one default formatting that is standardized and there should be the option to emit in other formats such that everyone can read in the individually preferred format.
With fmt you don't need to establish formatting rules on a project basis, anymore. Everybody can just configure their editor to format the code how they want it to look. That is why I think rustfmt should be compilable as a library, too.