They obviously didn’t invent it, it’s an USA import: both the TOW launcher and the HMMWV. It is however used by the LUX armed forces, and so far the only AT vehicle they ever had. So it could become a nice skin or vehicle to represent this country in War Thunder. The only (current) other option would be an Airbus H145M with 2 x 12-tube 70 mm FZ231 rocket pods (laser guided).
Probably because it’s one of only two anti tank capable ground vehicles Luxembourg has.
They made it as far as a subtree, one of their vehicles will be in the French tree anyways (since it’s French), so they might as well be nice to Luxembourg and add the one thing it can reasonably contribute to the ground tree.
There is a minor issue with, Luxemburg is not in the US tree.
Everyone I’ve talked to(that aren’t US mains) agrees that even if “C&P” the Luxembourg Humvee with TOW is a valid addition, as we’d get them as an operator nation.
Source here states that they were delivered to Sweden with their “Advanced equipment” and can be outfitted to something akin to the Israeli Battle Hawk, or UH-60L DAP. (Similar weaponry, also probably would be capable of SPIKE-ER’s like the battle hawk; as BAe Hagglünds has an odd affair with SPIKE’s) Source
NOTE: Notice the pylon mounting points above the front gunner door
Circled in red is the same point on the UH-60L DAP;