Matisse is very definitely a colorist by the simple definition of the term. The desire to complicate its meaning is not supported -- again, I've found no defintion in some major art textbooks and very little usage of the term. I'll go with the Google 770 hits on "colorist Matissse."
I don't know how many "artists" have come into my galleries over the past thirty years and the first thing out of their mouth is, "Look at my work -- it's better than what you have in here." If I condescended to looking at their work, I advised them not to give up their day job.
