That's pretty much the rationale behind every Air traffic System in the world.
Really TIEW?
You said this at post #21 in this thread:
How does CASA and Air Services decide whether an airport has a Control Tower?
Gove was also for a time the only place both mainlines of the day operated B737's into as RPT without a TWR. They also operated into Ayers Rock but they were classed as CHTR, so fell outside the regs. It was the potential for two 73's to be mixing it up with the local GA that drove the building of the TWR. While the apron could fit two at a pinch, the schedules had them separated, but often they were arriving and departing traffic for each other. It used to make me chuckle that while they would happily be spat out of the overlying CTA on descent, and left to work things out under "Directed Traffic", coordinating a pre departure clearance with DRW ATC involved much more to-ing and fro-ing so that they would be adequately separated prior to reaching CTA on climb (which I think was either at FL200 or FL250 from distant memory).
That’s the kind of irrational nonsense that used to prevail back then and infects the system to this day.
It was, indeed, chuckle-worthy nonsense that it was acceptably ‘safe’ for the aircraft to sort themselves out on approach OCTA, but ‘unsafe’ for them to do the same on departure.
It was, indeed, chuckle-worthy nonsense that it was acceptably ‘safe’ for 2 charter 73s to operate without a tower but ‘unsafe’ if one or both of them was RPT. Precisely the same objective risks to the 200+ precious passengers, but different air traffic system requirements. This nonsense infects the classification of operations mess to this day.