Why shouldn't the instance owner make that choice? It's their hardware, time, money, and desire that made that instance. As soon as I start one, first thing I'm doing is making sure it never gets federated with fashy instances or meta.
I like your points. The only part I think that could still be debated is definition of an artist. Actors and singers are considered by many to be artists (though of course the definition of artist is subjective), and we are far more likely to recognize them in their art than we probably are to recognize, say, a painter or sculptor, thus making it harder not to idolize them as artists.
EDIT: Seriously. As someone who isn't a hardcore militant FOSS federation activist, this is the kind of stuff that makes me want to throw up my hands and say, "Screw it. I guess I'll go sign up at Threads."
What is ricing