The big gubbermint types say that. The dealer quoted in the article sold illegal weed for 20 years. She is out of business. Cartel crap isn't imported to Colorado anymore.
Legal or not, weed has always been available. In all 57 states.
Of course, with legalization you don't have LE smashing down doors in no-knock raids looking for a couple of plants, so I believe her that more people are growing their own.