Postal service is very different from everything else you listed. The reason we're pumping so much money into those is that money should act as a significant multiplier for creating jobs and moving money through tbe economy.

Subsidizing the Post, while creating a better service doesn't have the same sort of multiplier benefit, other than the Keynesian hole digging style of employment.

I may not love the climate effects of some of these projects but from a "will these employ people and get a decent amount of money closing through the economy", the answer is pretty definitively yes.