"hey could choose to publish purely in open source journals and this would be a non-issue." These journals often offload the cost of publishing onto the author

"hey could choose to publish purely in open source journals and this would be a non-issue." These journals often offload the cost of publishing onto the authors themselves, and that money is tight. An open access publication is about the same cost as keeping an undergrad employed in my lab for a semester. And that ignores, as others have noted, that career incentives put "Only publish in open access journals" as the kind of principled stand that might kill a new researcher's career.