The author outlined why the m4 isn't the "primary" weapon. Bigger and better weapons proliferate the battle field. Putting it into car terms: it's like using a 1/2" ratchet when an impact gun is available. Sure you CAN put tires on with a ratchet..... But every single person would choose an impact.
Would I rather shoot, move, and communicate to destroy the Taliban? Or have a casual conversation with a pilot?
On my deployment we definitely used air power as much as possible to avoid casualties.
"warheads to foreheads" is the name of the game.

