I remember vaguely the quote "Art is what reveals something of you that you didn't know".

I suppose it would apply to both the "generator" and the "observer". This implies a process of exploring unknown territory, for both, the creator and the viewer. Both the act of expressing what lies beyond our daily existence and the act of internalizing it require not effort, but a state of mind, grace, or flow. The crux is always opening unexplored paths of mind and soul and exposing hidden parts of ourselves to that "light"

Assuming this, the fact of a public is irrelevant. You can express art without (or with) an audience and you can perceive art without an artist. I think photography is a good example of the latter, you put your attitude into a "peeker of the beyond" and see (create?) art in the act of seeing. And even, after some practice, you can become a photographer without a camera. In the same sense, you can view art in human creations that even their authors don't realize are art.

And now we are entering the uncharted territory of AI generated "stuff", where its artistic potential can only crystallize in an aware observer.

I'd say that the act of interiorization of art requires, to similar degrees, an object with potential and -this is frequently overseen- a special mode of perception, after all, we —at least I— cannot see 'a World in a Grain of Sand' every day :-)