At the root of this cognitive dissonance is who benefits and who doesn’t. Copyright law is selectively applied in a way that protects the powerful and exploits the powerless. In a capitalist economy copyright is meant to protect people’s livelihoods by ensuring they are compensated for their labor, but due to the power imbalance inherent to capitalism it is instead used only to protect the interests of capital. The fact that AI companies are granted full impunity to violate the copyright of millions is evidence that copyright law is ineffective at the task for which it was purportedly created.
Chill out a bit, my comment could not have possibly given you the impression that I’m a supporter of capitalism if you had read it carefully. I began my comment by putting forward the capitalist argument for copyright - a steel-man argument - and ended it by debunking it.
You said yourself that copyright establishes art as private property (or “intellectual property” if we’re being more precise). That does the opposite of fostering and improving the commons and public domain.
Then it wouldn’t be copyright. Copyright is a capitalist construct, not a public good corrupted by capital.