Military brass don't control procurement. That would be Congress. In fact the military often frequently has systems it doesn't want/need precisely because Congress. See the Zumwalt destroyer and the Littoral Combat Ship.
Who else are they going to buy planes to bomb different-colored countries with? SpaceX? Airbus? It is to laugh.
When you get a company that is too big to fail, it rests directly on the government for not identifying and solving the issue earlier.
The latest big bomber purchase, B-21, went to Northrop Grumman, as did the not so recent B-2. Fighters have been going to Lockheed (F-22 and F-35).
The biggest recent win for Boeing was KC-46 tanker airplane, which is just modified 767. I suppose there is also the handful of F-15EXes that are vestige from their McDonnell Douglas merger.
Politicians care about getting elected, which means they don't want layoffs on their watch. Politicians don't care what the military thinks or else they'd stop funding a lot of dumb projects that the military doesn't give a shit about - of which there are many.
There are so many examples of congress putting their hand on the scale that I really don't understand the popular insistence that the military is the problem here.