I got this comment on an answer of mine:
Parallel major/minor keys are not closely related. They are easy to get to, but not closely related. It's like you might live by a subway that make it easier to get somewhere, but you may not be close to the destination.
(A comment on this answer)
Parallel keys are three sharps / flats away from the tonic, and therefore, they are not closely related. Regardless, they are very easy to get to. What's the reason?