Are you guys serious? Yoda lived 900+ years and was supposed to be super wise... How would Luke overcome him in 30 years, biased fans?

The Republic and the Jedi Order fell on Yoda's watch, and he spent the next 20 years waiting for Luke to mature so he could clean up Yoda's mess. Yoda knew the Sith were coming, yet he allowed the Jedi to be spread thin across the galaxy, and he cared more about making sure Anakin toed the line than listening to his legitimate criticisms of the Order, even though Anakin was the only person in the Order who hadn't been brainwashed from birth to believe the Jedi dogma. Luke was wiser than Yoda by Return of the Jedi.