Possibly. But I have seen college itself (not just dedicated writing classes) help people write immeasurably. This is because writing is involved in most everything one does there. It's an extension of high school. Same concept.
My highschool courses were all graded on essays except the hard sciences. College is not the only place to learn to write. I also remember my 5th grade teacher telling me we all deserved As (for average instead of E for excellent) but that if anyone were to have an E it was me or this other girl. Writing is encouraged at all ages, not just college.