Wax would be used, I assume if one wanted to produce something like a flashlight by casting. I think these Chinese lights are all actually made on a lathe.
It would be interesting to see how long it takes a well-programmed NC lathe to make a Sipik SK68 or such. When I looked at a textbook on NC programming in a college book store, it discussed the inertia of the tool and holder, implying that the tools can move quickly. I imagine that aircraft alloy Al can be cut faster than that video and that not much time is wasted between cuts. Its high heat conductivity helps, but pure Al with the highest conductivity is probably too soft to machine quickly.
I think the TrustFire Z8 Review: TrustFire Z8 - XM-L Flood-to-Throw, must take several times as long, in stainless steel.