This is the real answer, public service always needs to serve the “underserved”.

Firefighters are public, their fire trucks are built for profit, the fire station is built for profit, their gear is built and sold for profit.

Like firefighters everything ATC uses and touches to do their job is a for profit provider, profiting off of taxpayer revenue.

There is nothing more “efficient” about being “not for profit”

The issue is the when the costumer can be defined by sales the it can be private and when the costumer is defined by community expectations then it cant be private.