The industrial spies in the West send back information that binary was used exclusively and the Soviet bureaucracy, like usual, decided that the West knows best and shut down that area of research.

One thing people in the West don't understand is that the Soviet Union after Stalin believed it was a second rate power and acted like one. In many ways the Politburo was a US cheerleader, they only challenged the US tactically while strategically accepting most of the propaganda more uncritically than US dissidents.