You are technically correct. In practice, I had colleagues working as "web designers" who were working right next to me and would not get a substantial part of their salary taken out for health insurance. So, they were still funded by the non-artists.
Why the distinction? Because this work involved Photoshop and mine used emacs?
As I said, the portion they don't pay is taken from companies using creative work. Not from you and not from me.
It is only available to freelancers. People working in those fields usually don't have the option of regular employment. For that reason was decided that companies using their work still need to contribute to health insurance (as all regular employers need to do as well). For everybody else the answer is: seek regular employment if you want someone else to pay half of your health insurance.
Alright, then. One could argue that the costs that companies have with this still get passed along to the consumers and other workers, but I will concede it is not "funded by us".
Still does not explain why there is a distinction. Why do artists get to have companies paying them part of their social security while other freelancers still need to make this out of their own pocket? If this is a good idea for the artists, why not for other professions?