What's incredibly exciting about USB power delivery is that it offers a glimpse at a future world with a common, unified electrical socket. If you go into a house, and there's a USB-C port on the wall, it can be used by anyone, anywhere in the world, for anything that charges through USB-C.
Sure, at the moment, the supported voltages are relatively small. But over time, they will increase, and more and more gadgets and appliances can be powered through USB-C, the utility (network effects!) will only increase.