yeah OBD and whatever maker-specific extensions, because lots of things only work that way

Having said that, it’s probably only an issue when taking to the dealer for anything. Your everyday, local mechanic likely only cares about the diagnostic codes that might be active and point to the issue at hand.

used to be! but nowadays manufacturers are upgrading their diag software with DRM, that these tools refuse to work without internet. and this has been going for years now as I know. and sometimes the mechanic needs to pull up that diag software, because the other one does not tell enough, or maybe they are just always using that because it’s easier for them