I did some observation on Dune Sea and every vehicle spawned in damaged, so I guess that's how it's intended to work? I think it can be hard to gauge if it works on a map or not because a lot of vehicles spawn right next to repair droids. Edit: Was also able to confirm it working on Platforms and Harbor.

Nice to have confirmation on it working. In similar news, discovered how to get Sabotage working on PC by turning friendly fire on.