All of Apple's "accessories" (things that will request charge from a host over their cable: phones, tablets, keyboards and touchpads, and now headphones) have a Lightning port.
All of Apple's "computers" (things that won't: computers that are wired for power, and devices that are wired for power like the Apple TV) have, or will have, USB-C ports.
The vague middle case is laptops, like the new MBP: they do charge over their USB-C cables. But they'll only do this from a wall-socket power adapter; they won't attempt to drain the battery of a peer device they're connected to.
Besides that HCI hint of charging semantics, though, Lightning is just physically different in a few important ways that Apple relies on: for one, the connectors are solid metal, so an upward-pointed male connector can be used as a freestanding dock. That's not true of USB-C. Apple isn't going to converge them.