First, full disclosure: I am an art cretin.
For me, art = story.
That is: an abstraction or extraction of the essential elements of some human experience, "real" or imagined; then rendered by sound, sight, touch, taste (one or more of those) by one person - a transmitter - to generate a mental image to the receiver, that is hopefully similar to the transmitter's originally intended image - which seldom succeeds perfectly.
If it (the artifact) tells me a story, I feel like I "get" it. If it doesn't, then communication failed (maybe on my part, maybe on the sender's), though it may still be "art".
I "get"
It speaks to me across 17 thousand years of humanity, though it's crude and childlike. The story 'Grogg', the artist, intended, and the story I think I understand may be different, but the mere fact that his (her?) wall-scratchings inspire an image (and story) in my brain makes his/her effort - not required for his/her individual survival - "art".
And AdrianII's specimen
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