Only if the device's consumption is < 2.5W, which is what a USB 2.0 computer USB-A's data port limit is. Anything above that, compliance gets a bit more involved and complicated.
Yes, but that's the case with microUSB as well. In fact, refusing to work with underpowered source is easier with USB-C.
Yes, but that's the case with microUSB as well. In fact, refusing to work with underpowered source is easier with USB-C.