I think this can be seen a bit like the invention of an "index fund" for art. Active investors are still needed to generate the market signals that an ETF can a

I think this can be seen a bit like the invention of an "index fund" for art. Active investors are still needed to generate the market signals that an ETF can aggregate, but for the majority of people an ETF is preferable to the cost of hiring an active investor yourself. And similarly SD needs artists to generate the signal that it aggregates, but for the majority of people it might be (or might soon be) preferable to use SD to get a "generic"/"average" result instead of hiring an artist yourself.