I think it would be much worse if artists, writers, scientists, open source developers and so on were forced to stop making their works freely available because they don’t want their creations to be used by others for commercial purposes.

None of them are forced to stop making their works freely available. If they want to voluntarily stop making their works freely available to prevent commercial interests from using them, that’s on them.

Besides, that’s not so bad to me. The rest of us who want to share with humanity will keep sharing with humanity. The worst case imo is that artists, writers, scientists, and open source developers cannot take full advantage of the latest advancements in tech to make more and better art, writing, science, and software. We cannot let humanity’s creative potential be held hostage by anyone.

That could really mean that large parts of humanity would be cut off from knowledge.

On the contrary, AI is making knowledge more accessible than ever before to large parts of humanity. The only comparible other technologies that have done this in recent times are the internet and search engines. Thank goodness the internet enables piracy that allows anyone to download troves of ebooks for free. I look forward to AI doing the same on an even greater scale.