This certainly seems to reduce how much experience and study an artist needs to have in order to produce art. And I think it's likely to reduce how much the viewer values the product as well.
Automation does not always increase demand for the jobs being automated. Tractors didn't create more demand for oxen than ever.
The number of people working in agriculture was divided by c. 6 in the US [0], despite the population being multiplied by c. 3.5.
Sure, automation increased demand for food, but demand did not increase enough to not destroy 5/6th of farmers jobs.
Now this may not be a bad thing at all, that's not the point, but I am not sure "hey demand for art will increase but 5 out of 6 artist jobs will no longer exist!" is a super hopeful statement to artists.
Yours is a different definition of demand than the economics definition, which is basically the amount customers will buy as a function of price. Higher demand means buyers will pay a higher price for the same art.
Automation increases supply, which increases the volume of art consumed, mainly because it is available at a lower price. That is shifting to a different point on the same demand curve, and doesn't mean that demand has increased.
Just look at the dairy industry. Pre-automation sales numbers vs. post-automation sales numbers.
This is true for every industry on earth, and doesn't care about the pedantic definition of demand. Consumer demand = more purchases. More purchases = more revenue.
To refresh your memory, the context of this thread is that JimDabell argued that software automation increased demand for software programmers, and the same will be true for art. I responded that there's no guarantee of that, and then you pointed out that it can't be stopped. Which may be the case but it has no bearing on the question of whether artists will lose their careers. Just because it's inevitable doesn't mean it's not a cause for legitimate concern.
Automation does not always increase demand for the jobs being automated. Tractors didn't create more demand for oxen than ever.