It's been pretty common to include arts in with STEM for a while, at least in the parts of the internet I inhabit. I know Adam Savage has used it for a few years on his YouTube channel.
And I'm personally a fan of it, I see art as just sort of applied STEM. Not everyone is going to be doing high-level professional STEM work, but at some point nearly everyone is going to paint or decorate something, try to fix or build something, etc. and it's going to be helpful for them to understand what kind of glues, fasteners, paints, etc. are going to be useful for their intended application.
And art is also a pretty effective gateway to getting kids (or even adults) interested in STEM. If you plop a kid down in front of a computer and start teaching them PYTHON out of a textbook, they're probably gonna be less than enthusiastic. But if you start by having them draw a cool robot, then have them build it out of a Lego robotics kit and help them to figure out how to make it move, you're probably gonna have a lot more success getting them interested in programming.