Nobody wants to care about copyright, but everyone has to.
Research is tough. Critical comments from peers, rejections. When accepted, the article only gets published if you sign the license agreement. Re-negotiating is tedious and the agreement is the thing keeping you from publication—maybe even tenure. You sign it without considering the consequences. But the major consequence is that your work is now locked up, which directly affects the impact of your work. Princeton University has even opted to not let researchers handle copyright agreements, because of the consequences.