"skill acquired by experience, study, or observation" - does that mean that when I learn to butcher a pig by watching youtube videos of it, it becomes an art? Of course not. "art" implies some form of subjective addition to it, usually for a "higher purpose", not just functional (I'm not trying to come up with a definition of "art", as whole libraries have been written about it, I'm just stating that you implying that anything that is learned in some form is an "art" does not correspond to the common usage of the word).