I frickin' LOVE matte art in movies. I think the last time I saw one was... omg... Idiocracy?? In 2006? I actually sat up straighter and said "Is that a matte background?"

I think technically it's still in use, but in conjunction with a lot of digital and CGI. So yeah, probably "matte artist" on its own is no longer a thing. But television is getting so design-y and niche, when it has the budget. Maybe we'll see a renaissance one day!