The logical conclusion is that "digital art" is an oxymoron, since it allows exact copies, indistinguishable from originals.

If you record yourself playing the violin, but digitally, that sequence of easily reproduced bits isn't a work of art, just a copy: the first copy, of which there will be a second and so on.

Also, literature cannot be art, because the words themselves are the poetry or prose, and not the specific representation in orgiginal handwriting or typesetting. When you read an author, you're not really reading the art, but a copy of the art.

A handwritten manuscript may be a form of visual art, but what if the manuscript was produced with a generic typewriter, or digitally ...

Then how can the "original" painting be a work of art? It's just an artifact of an act of creation. If art is in the act, then the artwork is dead as soon as it is finished.

Suppose I own a piece-of-art and a copy. I swap molecules between them gradually, until the original no longer has any of its original molecules, and the copy has them all.

Which is the piece-of-art?

The art world probably has bizarre ideologies because they serve as investments and status symbols to elite patrons/customers. (And while the artist lives, they'd like to get paid. But our world isn't dominated by artists, so their subsistence isn't considered as important.)

I'm not sure why you have been downvoted. I think the sentiment you're expressing is a very common intuition that people have about art. It's uncomfortable to think about, because it leads to the logical conclusion that art is really about status rather than about the work itself. On the other hand, if art really is about the work itself apart from considerations about status or historical context, then art is no longer rare; there's great stuff everywhere.