https://www.theguardian.com/science/political-science/2018/j...
In the meantime, it would be nice if everybody uploaded their reviewed papers to arXiv. No one should have to pay for new content already been paid by the taxpayers.
In Germany, there stands nothing in the way of all the professors and students simply republishing their work elsewhere and Elsevier could not nothing about it.
What they can't do is publish copies of works that Elsevier has edited (significantly). So if Elsevier contributed to the document then the editor as Elsevier and by proxy Elsevier has the copyright on those parts IF they are significant enough (significant is a huge burden of proof here, spelling mistakes being corrected don't count).
The publisher to my knowledge cannot claim copyright over composition, layout, typesetting or the PDF unless they can show they had significant copyrightable work in each step. (Copyright in Germany first requires you to do some significant intellectual work, where significant changes based on what you do but science usually has a higher barrier)
If the PDF contains a trademark of theirs then that's a problem.
Generally a pre-print PDF should be available in almost all cases and could be published without Elsevier's input. If not that, Universities do archive the Tex files (or similar inputs) if possible so they could take those.
I think Elsevier can achieve temporary stalemate at best.