The problem in your analogy is you don’t think Lady Gaga is worth paying close attention to. Substack’s proposition is that an individual writer has an audience willing to pay to read much or all of what the writer publishes. It’s not a business model seeking dabblers on either side of the transaction.
Good way of putting it. Substack, as currently positioned, is for people who are sufficiently motivated to pay the equivalent of a traditional magazine subscription for maybe a few writers who produce engaging content, presumably on a frequent basis, that they find worth paying for relative to free alternatives.