well, technically speaking it is. A reduced life results in the asset having to be amortised over a shorter period with a reduced value at the end of that period, which makes the aircraft more expensive to operate. That makes it a fundamental flaw in the design as potentially it affects the operational cost to the user, which is the result of the actual 'design'.
Don't agree. A technical design issue that results in a changed operational cost is one thing, but this is a manufacturing problem. Correctly manufactured models will perform to specification (excluding other issues), so this is purely a programme issue.
The subcontractor in this case however is Boeing South Carolina.
...and Boeing South Carolina was previously Vought, a subcontractor, that Boeing decided to buy out, because of...programme issues...