If we didn't live under an economic system where creatives need to sell their works to make a living or even just survive, there wouldn't be an issue. What OpenAI is doing is little different than any other worker exploitation, however. They are taking the fruits of the labor of others, without compensation of any kind, then using it to effectively destroy their livelihoods.
Few, if any, of the benefits of technological innovation related to LLMs or related tech is improving things for anyone but the already ultra-wealthy. That is the actual reason that we can't have nice things; the greedy being obsessed with taking and taking while giving less than nothing back in return.
Just like noone is entitled to own a business that can't afford to pay a living wage, OpenAI is not entitled to run a business aimed at building tools to destroy the livelihoods of countless thousands, if not millions, of creatives by building their tools out of stolen works.
I say this as one who is in support of trying to create actual AGI and potentially "uplift" species, making humanity less lonely. I think OpenAI doesn't have what it takes and is nothing more than another scam to rob workers of the value of their labor.