Ordered list of reasons I don't believe anything worthwhile will happen:
1. Boeing is a huge defence contractor with both civil and military products sold worldwide. A big loss to Boeing will be seen as a big loss to American hegemony.
Actually you could argue having one of your biggest defence contractors behave like this is a bigger loss to American power than holding their feet to the fire and trying to develop a more engineering focused culture.
You forgot one thing: Boeing is not only under FAA and US scrutiny, all their processes and planes are certified by EASA, and others, as well. The B737 Max crashes alread harmed the trust between EASA and FAA, if nothing happens now, EASA might very well take seperate action. I have a hunch Boeing doesn't want that.
Edit: There is also a couple of high ranking people that are "holders" of those certifications, Design Organisation Approval and Production Organisation Approval in EASA parlance. Forgot the exactvtitle of those people, but usually they aee at least VP level, sometimes even C-level and always a seperate one from Quality. They are vetted by the national authorities and sign to confirm their obligation, incl. legal, to adhere to the stabdards and do everything to meet those. In Europe, negligence of this can lead to criminal prosecution and jail time. No idea how this is done under FAA regulations. Boeing peopably doesn't fall under EASA jurisdiction in that regard so, having not operations in Europe.
I think that would "only" affect the broader foreign policy.
My take is that arms trade is a good business (my assumption) and unprincipled foreign policy could see more indiscriminate trading taking place. I.e. the opposite effect.
And what's the point of having US weapons, when USA won't give you ammunition because it decided it would be escalatory? Swiss arms industry is having same problem, but there it is stemming from neutrality of Swiss government.
1. Boeing is a huge defence contractor with both civil and military products sold worldwide. A big loss to Boeing will be seen as a big loss to American hegemony.
2. GOTO 1