So where does it say QM was not studied for 30 years because of Einstein?
If you're exclusively reading Scientific American for info on the history of the field, you're going to be fed a lot of mistaken information. It's an excellent source for pure science (Gordon Kane's articles on physics are some of my favorites) but it's very erratic when it comes to chronicling the history of science, and completely worthless when it comes to discussions of society and policy.