@Firv, with other late-game upgrades, you get maybe a few minutes of value before the armies become too big to face, whereas billy you can potentially keep using to good effect almost indefinitely right now, sitting cozy under shields behind percy walls, lobbing rockets across the map. The risk hardly increases as the game progresses, like it does for other com upgrades, since there's not much incentive to get anywhere close to threats in order to use it. In addition, because armies tend to get bigger and less wieldy, the care you have to put into your aim actually goes down as time goes on. Plus, you can pair it with t3 which is a defensive upgrade. The change I suggested wouldn't mean you absolutely must bring the com into knife distance either.
Also, it doesn't impact tele billy at all, because in that scenario you're shooting at helpless and static targets. If you're hunting armies, teleporting is actually worse than airlifting because you can't adjust your destination as the move orders shift around plus your fire rate is shit.