Unless the DoJ splits up Boeing, which is what they should do. If Apple's iPhone is a monopoly with dozens of Android alternatives, what does that say about Boeing?
The DoJ doesn't want to split up Boeing, because then it'll be even less competitive against Airbus. Economies of scale are important in large manufacturing operations.
Boeing at this point is a sort of nationalized industry.
If a car manufacturer pulled something like this they either have to fix it really fast or have to face severe financial consequences.
You have to realize that Boeing's customers have no alternative. They will be buying planes from Boeing.