I have mixed feelings. I loathe instapoetry as much as any modern poetry reader... However, I also hate that every modern poetry demands readers to read "good" poetry first to understand why instapoetry is bad (spoiler: instapoetry lacks depth).
My impression is that his books sold in places where other poetry wasn't, e.g. card stores. But it has been a while since I've seen his poetry anywhere.