Yes. They absolutely were. Sanders supporters lit every other candidate on fire for their past failings. This was one that was on the top of their list for her. And I firmly believe that Biden is merely trying to stop this from occurring to him.
Especially because the stuff at the University of Delaware--which he might have some sway over--is just his personal letters and documentation. This isn't even to mention that the stuff there hasn't even been fully processed yet. The important information is sitting in the National Archives.
https://www.cnn.com/2020/04/30/polit...ers/index.html