One cannot rule out the possibility that the PLARF has pulled out the vast majority of DF-41s and DF-31AGs from their strategic deployment just for this parade. They still have DF-5 series and the older DF-31s on deployment while the DF-41s and DF-31AGs celebrate the national holiday in Beijing. Putting up a good show with zero mistakes is directly relevant to the legitimacy of the CCP. In China, the image is sometimes more important than actual reality. Having both Chinese citizens and outsiders BELIEVE that the PLARF is an almighty force (along with the CCP being perceived as undefeatable) is much more important than whether or not the PLARF is almighty. Also, the PLARF has a very limited arsenal of warheads (260-280). There seem to be more rockets available than warheads. Additionally, I don't know if China still produces or has enough weapons-grade plutonium and tritium gas to produce more than 500 large-yield (>100 kilotons) warheads. Jeffrey Lewis said back in 2013 that China does not. Lastly, as Dr. Lewis mentioned in one of his older books (The Minimum Means of Reprisal), the CCP emphasizes the CMC's absolute CONTROL of every single nuclear warhead, so more warheads mean increasing difficulty in management. The last thing Beijing wants is to have a single rocket with warheads attached falling into the hand of a rogue general losing in factional struggles over promotions, political influence, or economic interests.