I have an Anker USB 3.0 (USB Type A) charger that can output 5V/2.4A for a maximum of 12W per port.
When I charge my iPhone with a USB-A to Lightning cable, it pulls the full 12W.
But when I use a USB 3.0 Type A to USB-C cable to charge my M1 MacBook Air, it only pulls 5W from the charger...