Please, let's return to the golden age of when I was in college and professors had to write things illegibly on the chalkboard before just reading them to us!
In mathematics that is still the preferred method, because (latex beamer) slides have far to little space to capture all the stuff you want to view in parallel to e.g. understand a proof. Additionally it forces the lecturer to slow down the information flow, which is equally important in mathematics.
In less complex subjects I would prefer slides and well written lecture notes. What Rebecca Schuman is criticising are slides that are simultaneously abused as lecture notes.
