How could a neutral observer find that communist theory or communist institutions (or both) were successful in certain ways even though communism has "fallen?"
A neutral observer could argue that communism allowed countries like the Soviet Union to become relatively strong in a very short period of time. A neutral observer could argue that the Soviet Union's command economy did a much better job of turning the country around and industrializing it than any democratic government could have done. The same could be said of China in the Deng Xiaoping era. From this point of view, the main success of communism was that it was able to force its people to industrialize their countries in ways that would have been very difficult if the people had had more freedom of choice.
The neutral observer might listen to Harold Bloom opine about how he moved from the English Department to the Humanities Department because of the way Marxist ideology was used to criticize literature.
With that in mind communist theory must be alive and well in College English Departments.
And I say that as a person who would read professor Bloom even if he doesn't like Harry Potter.