In short, horse trading. That is, if you have leverage in an adversarial negotiation, you'd be foolish not to use it to get more of what you want.
For example, as a prospective employee, if I knew that I was the only qualified candidate the employer had interviewed, and they really needed someone within a week, I'd know that I can ask for more salary. If I instead take the middle of the salary range, just because it's maximally acceptable to both parties, I'd be missing out
Fascinating. Air traffic controllers shouldn’t be a bargaining chip. Planes must keep flying. If the US federal government is too dysfunctional to provide this service (which it is paid to provide), it should be stripped of the privilege of providing it and some other entity should step in to fill the gap. “Shutdown” should be an abdication of sovereignty plain and simple.
Any "other entity" would, in practice, be either beholden to the same government, or concerned with profit over safety.
Our current crisis is not one we can or should base new structures off of. There is no realistic way to run a modern society that can take into account a government utterly hostile to the very notion of governing. We have to get rid of the bad actors and restore some semblance of sanity before we can even consider how to make things more robust against this sort of treasonous single-party capture in future.