Boeing messed up, but it’s happened before. Building airplanes isn’t easy and only 2 companies do it with any large scale, each of which had engineering challenges which they fixed. The original 737 had a rudder problem too. Airbus had the “side stick” drama that doomed Air France among others.
You don’t always get the benefit of knowing what “would have” happened if they had done X or Y. Boeing was punished for their mistakes, the CEO lost his job, people lost their jobs, money, and lives. They are going to do everything they can to fix it.