The "proprietary charging port" is a) optional (you can also charge on the USB-C ports up to 100W), b) extremely handy for those of us used to the old magsafe p

The "proprietary charging port" is a) optional (you can also charge on the USB-C ports up to 100W), b) extremely handy for those of us used to the old magsafe ports, and b) actually a USB 3.1 port with extended power range in disguise. The power brick that ships with the Macbook Pro is a USB-C wall adapter. The magsafe cable is USB-C on one end and magsafe on the other. The extended power range spec allows going up to 240W instead of only 100W per the original USB power delivery spec. The 16" Macbook Pro can draw up to 140W. There aren't currently available any standard USB-C cables that support extended power delivery. The higher current requirements entail more robust cables that will have a compatibility marking on them.