No, the nature of this discussion puts the onus of providing evidence squarely on you. You are the one making the spectacular claim that is going against general common sense and challenges the null hypothesis here, so you are the one that has the make the evidence, and you don't have the right to demand others to prove a negative.
But I'll indulge you a little.
It is very obvious why a nation that previously has produced very few commercial aircraft may seek foreign companies with experience in commercial systems (with the requisite experience in certification/regulation, commercial maturity, and commercial commonality) to provide subsystems for a commercial aircraft. That's because the flight control system/FBW system (or indeed, any particular subsystem you want to think of) for a military aircraft -- regardless of how much more sophisticated it is compared to that of a commercial aircraft -- does not have to meet those same commercial criteria to try to achieve commercial success with minimal risk.
The logistical, certification, marketplace and customer requirements for a flying wing stealth bomber is massively different to a small or medium sized commercial passenger aircraft.
In essence, you are mistaking customer and marketplace requirements of commercial aircraft and equating it with wholesale technological advancement or capability, and your entire argument only makes sense based on that assumption.
I don't know why you've chosen this particular this hill to defend, but I commend your persistence.
