I think it’s not very hard; if the AI companies believe the data they trained on is public domain/open because they scraped it of the internet, then their trained weights must publicly available as well. They cannot claim ‘but training is expensive’; if they do, then they should pay fees for the hosting and storage and writing time of all data they scraped. I prefer open weights as it’s more practical. Your weights have a sliver of GPL source in it? Well that infected the entire thing as GPL does: it is ours now too!