Because as we are literally discovering, not knowing the details of how and why the automatic stabilization software is driving your trim wheel can kill you. The biggest single part of the failure chain here was the fact that this should have been an invasive change requiring recertification as a different aircraft and retraining for pilots instead of pretending that it was just like a 737-600.
You are on my page. Type certification is the process to discover issues like this.
I'm not familiar with pilot training and certification but it seems to me that even if the 737 MAX was type certified certifying a pilot with previous 737 experience would have been just supplemental training. Ultimately a nothing burger.
I've seen a lot of cases where people get bent thinking of all the bad things that will happen because they think customers won't like some change. Always in the end if it's not a show stopper the customers just lump it.
