The problem of pork barrels is that it gets them votes directly by making things worse for everybody else in exchange for local benefits. Disproportionate representation is what enables it as a tactic or at least makes it more disastrous. Something which serves the interests of 30% of the population is closer to benefitting the whole than one for 3% of the population.
In the modern environment, material pork barrel spending is at the corporate/national level. Most congressional districts due to gerrymandering or demographics are very secure... the era of political machines handing out turkeys is gone.
If the craven corruption around defense contracting was only 80% as wasteful as it is today, you could give every member of congress a substantial slush fund to waste and still save money. Plus you would have working fighter jets that are able to compete with countries like Russia, that has a GDP equivalent to Texas but seems to be able to procure weapons.
Because Members of Congress basically need to continuously raise money, there’s always an incentive to spread the wealth among congressional districts.
For the F35, I can think of one company in a rural area who fabricates some metal component for the project. Because of the way it is contracted, acceptance standards, etc they sell it for something like 50x it’s value of you were to order it, and whomever gets the part spends even more to receive it.
Planes are small and have lots of parts, so they suffer more from these issues. We’re still ok at building warships, because you can’t build a shipyard in some coal town in Kentucky.