Well "do not admit fault" is basic advice that is printed on every auto insurance card and something that any lawyer will tell you for free. Do they really except the CEO of a large multinational company to just randomly say "yeah, it was totally our fault, sue us"?
Muillenberg's assurances that they will fix everything on their own are not very convincing. The existence of such a terrible design -- a single sensor that has complete control over the horizontal stabilizer -- points to one or more teams or management chains within Boeing that are turning out shoddy work. They have undoubtedly turned out other shoddy work, and will likely continue to produce more shoddy work that will kill more people. An outside team needs to be brought in to investigate engineering and management. Immunity against lawsuits and job losses need to be assured, but we need to discover exactly what led to this so more terrible engineering ideas don't find their way into the next crop of airliners that we will be trusting our lives to.
The issue with the MAX8 is that it is fundamentally imbalanced. The larger heavier engines are tacked on to an airframe similar to the existing 737, constantly causing the plane to tip forwards, such that repeated tiny changes are required to maintain level flight. It is these tiny changes that are automated by software and can cause a crash when fed faulty sensor data.
The MAX10 is a significantly longer aircraft. The forwards rotation of the larger heavier engines is better balanced by the forces imparted by the tail acting over a longer lever arm, so the problematic sensor-driven software-controlled tiny changes aren't required.
The admission would tank Boeing stock, and invite a barrage of lawsuits. This is a delicate line to tow, that of providing for tens of thousands of employees, versus providing closure to loved ones of the dead.
