IMO you are vastly underestimating the long term damage this is doing to Boeing. In the short term, 737 user will have to keep using it and will have to buy more of those planes from Boeing, because switching to another single-aisle plane would cost too much and there simply isn't enough production capacity in the world to make this switch happen in the near future.

However the 737Max is the last version of the 737. 737 users will have to transition away from this type in the medium term future. The current troubles force them to think hard about whether they will trust Boeing at that point or decide to go with a competing product. Of which there will be roughly half a dozen by that time.

It gets even worse, if we look at the big picture. The 787, 747-8i and 737Max have all been expensive disappointments for the airlines that ordered them. Boeing has been losing market share to Airbus for decades now, this really isn't a good trend for them. That doesn't mean that Boeing will not find a certain level of success with their next airplanes, but the damage their brand has suffered does hurt their bottom line quite severely.