There are already strategies for monetizing OSS, like selling GPL exceptions or support, but it's up to the individual developer to figure this out. The OSS ecosystem could do more to encourage monetization. For instance, GitHub could add a "buy" button with payment processor for maintainers to easily sell closed source licenses. Package managers could include payment options too. It's not just about payment either, but they could also offer prewritten contracts and other legal templates for maintainers. I can easily envision a world where maintainers are properly funded. I suspect, however, that enterprising forces would prefer OSS remain charity work.