I must agree. Grand Strategy games like HOI4 can lead people, myself included, to assume some things are equal when they are not. Trained, experienced NCOs and soldiers will outperform a green outfit in everything from equipment maintenance to maneuver, attack and defense, and everything in between.
Take something as "simple" as movement. In the game we tell a division to move and it moves. Once it gets there it actually arrives completely in tact and ready to fight, for the most part. In real life it is not like that at all.
Imagine a Chinese division that has no professional NCOs, untrained lower officers, and missing middle level officers. That division might need half a day just for the movement order to get drafted and disseminated to the units. It will surely take another half day or more for those units to locate most of their men and equipment. It might be a day or more before any real movement toward the destination is started and it will be in fits and starts.
Movement orders are not magic. Just organizing the logistics and traffic flows takes professionals a lot of time. Take out the professionals and it is not movement. It is chaos that sorts itself out through the currency of time and cohesion. When the unit arrives it is a hot mess. It takes time for the few good leaders in the division to get around to each unit and sort them out. It is why non-professional/under-funded armies have to dumb down their organizations and reduce expectations. Grand strategy games make it seem like it is not important at this scale of the game, but it is an illusion.
If the game made us wait days for a Chinese division to just wake up and start moving, many of us would complain, but we would be learning something that is real. The French generals estimated the Germans would take much longer to move their divisions through the Lowlands than they did. They assumed the Germans were as slow as they were to maneuver. It was a fatal error. The Germans were able to send orders on the fly and the divisions responded so fast it changed warfare. this included the infantry and panzer divisions.
In
@Zauberelefant 's example above, he talks about some German NCO's from a NCO academy getting pulled into action in 1945. In 1945 the Germans were falling apart, yet they were still running the NCO schools to the bitter end. It is just that important.