This aligns exactly with what I expect is the real truth. I have doubts there's any actual killswitch because that'd be dumb - but a constant devouring of proprietary parts is absolutely the case.

I maintain that what actually happened is an airforce general bragged to Trump about how every F35 sold means decades of political dependence and service fees that would act like a kill switch to keep our allies in line and Trump heard the words kill switch and just ran with that.