What would you suggest as a more efficient way to achieve this goal? Building thousands of advanced fighter jets for private citizens? Keeping highly skilled engineers up to date on the most modern technologies and maintaining specialized factories is inherently expensive. You can't leave the factories mothballed because you need to keep the skilled workers employed and practiced with manufacturing.

Maybe there could be something like a weekend warriors but for machinists? One weekend a month, one week a year you build fighter jets. This does mean there needs to be private sector demand for those skillsets so the reservists have relevant day jobs.

Rather than the sarcastic non-answer, you could just respond to the question as asked.

Is this an official goal, or at attempt to handwave away the fact that we seem to waste trillions and decades to get anything done?

You would be hard pressed to find an official document that says it bluntly, but analysis of the situation makes it clear.

https://www.csis.org/analysis/why-us-defense-industrial-base...

Have legitimately successful aerospace companies that sell to other places, and create dual-use industries like autonomous driving with more DARPA challenge type stuff

My question is genuine.

Not really the point, but an idea that springs to mind is selling fighter jets to allied countries.

This is messy. The countries that could afford to buy the jets generally have domestic industries they want to protect, and you never know when some President will come into power that is hostile to that country and tells the contractors to stop supporting that very expensive hardware. There is precedent for this: See Iran's fleet of F-14s.