Boeing just isn’t the company it used to be. The lack of competition has really taken a toll. Couple it with the non-existant regulator and the ingredients come together to create the current situation.
Previous posters nailed it, the merge with MD and the move of HQ away from the factory floor were the beginning of the end. Extremely bizarre moves that started the chipping away that destroyed an American icon.
The Max is not the first warmed-over failure. Remember the 747-8? An accountant’s creation, just a modified 744 done on the cheap and fast. Going on over 10 years in service and still having FMC issues.
This is what happens when you let accountants build airplanes. You will succeed at only building the plane as cheap as possible.
The Max would be over and done with where it not for the lack of competition. Any time a competitor pops up, B and A buy them and integrate them. The new Embraer and C-Series killed the A318-319 and B-736-737. With time, they would have chipped away at the 320-321 and 738-9 line eventually, which is why they are now folded into the big two.