This is not true. I've never heard of a 'working class' person getting sued for copyright infringement. People who run a business to make money from copyright infringement are not working class and those few small timers who are infringing among family and friends would never be pursued; there is a 'fair use' clause after all in the US and the issue is re-distribution, not consumption.
The problem is not that copyright protects the powerful, it's that copyright is not enforced to protect you if you're not powerful. As is the case with AI. The problem is lack of enforcement so the idea that copyrights oppresses the working class is completely backwards.
I'm an open source developer myself. One of my projects has about 6k stars on GitHub. Open source is dead. It was never 'open' anyway because it was always the big corporate-sponsored projects which got all of the attention.
Frankly, open source is immoral at this stage. Just a con to convince gullible fools to give away their time for free for AI to use. Given the new reality, author is essentially unwittingly trying to steal people's time.
I'm not saying this as an insult. I do consider my past self to be a gullible fool, even before AI, though you have to recognize that I was a lesser kind of fool. Now the exact mechanism of theft of your labor is right there in front of your eyes! What a fool you have to be to write open source code now!
There are other ways to make code 'source available' where people can pay a contribution to use the code or participate and can become shareholders of a shared venture or member of a club. Paying contributors is the only moral approach. It's satanic that open source folks have flipped this basic, obvious moral reality on its head and it reveals deeply distorted personal values or a deep misunderstanding of how society functions and a deep hypocrisy around the role of money in people's lives and how it affects their ability to form groups. Many played right into the hands of the people they claim to oppose.