not arguing against you but maybe one takes the view that artists should not need to be self-sufficient purely from market forces and selling art? Maybe society should just subsidize them to an extent (this is obviously already happening but I'm saying as a matter of principle)
99.99% of artists definitely CAN'T make a living off only their art, but most can survive anyway by some form of other employment. Even though some small degree of government subsidies will always be around to help artists, and perhaps that's a noble principle, I'd just rather see my tax dollars go to health care or trade schools or food banks or child care or disaster relief or Meals On Wheels or medical research or similar efforts to help those in desperate need, instead of to artists choosing to be artists. There's always someone worse off than an artist, through no fault of their own.
The problem with subsidizing a portion of the population based on the chosen line of work is that we will never all agree on what exact work is worth subsidizing. For example, there is a lot of "art" that I think is completely worthless. Why should choosing to go into art mean that your output is not judged by market forces while someone who does the work we all depend on for survival and convenience has to worry about making ends meet?