I don't like the proprietary protocol, but actually there is a good reason for this communication between the charger and the laptop.
There are multiple charges with the same barrel jack, but different wattage. You plug a low wattage power adapter to a high powered laptop. Without the chip: The laptop can draw to much power and in the best case scenario it damages your power adapter, in worts case damage your laptop or burns down your house. With the chip: the laptop can throttle, so it draws less power.
USB Power Delivery does the same thing, just without the properitary protocol.
There are multiple charges with the same barrel jack, but different wattage. You plug a low wattage power adapter to a high powered laptop. Without the chip: The laptop can draw to much power and in the best case scenario it damages your power adapter, in worts case damage your laptop or burns down your house. With the chip: the laptop can throttle, so it draws less power.
USB Power Delivery does the same thing, just without the properitary protocol.