Do you know anything about Marx? Of course he was an economist and a philosopher. It seems to me that you really do not understand Ayn Rand at all if you equate her career and writings with Marx. Ayn was not an economist, no one considers her an economist. Marx on the other hand was one of the most influential economists that ever lived.
Mussolini and Hitler were influential as well. That doesn’t mean someone’s work is GOOD.