I understand it's a bad argument because 1) people may need assistance to do art/writing and 2) the advancements gained from teaching AI to do art can be applied to other non-artistic endeavors (e.g. piano AI could be really good to operate machines with lots of buttons and no computerized interface).
However, the cost cutting side of the argument is the one that bothers me because companies/people WILL use AI like that in place of actual humans because they're likely to be cheaper in the future. So that pianist or musician playing in a local restaurant can be sure their job will be automated away by a subpar AI and real humans will be relegated to very expensive locations (an extension of replacing humans with recorded music, in a way).
My pessismist side thinks greed will be the downfall of humanity.