what (rear) track/fixed hubs are currently being made with hollow axles for QR? just curious...

i think most people ride solid axles with nuts because that's how their fixed hub came and they don't care (or have the skill) to bother swapping out the axle. manufacturers take advantage of the appeared preference for track nuts by predominantly producing them. it's a microcosm of the fixed gear boom as a whole. if you can make something using a cheaper process (be it solid axles or no gears) that is just as (or more) desirable as a product of more expensive manufacturing process then it doesn't take a genius to figure out that you better get on that ****.