How could it not be? Your plane's location data is just as personal as your car's, or your cellphone's. There's no special aircraft exemption in the GDPR.
A big reason these jet accounts were popular is people enjoyed calling attention to how wasteful many of the flights were, which I can’t imagine Elon was unaware of.
There are services you can pay for (in the US) to track a car’s (almost) real-time location without gps. It’s based upon license plates and widespread webcams and it’s not illegal (yet).
A plane is not a person, a phone, a car, or a home. Elon Musk is often the passenger on his jet, but I am quite sure he is often not on board while it moves around.
> Why would a plane be treated differently than a car in a GDPR context?
A car is generally registered to an individual. A plane isn't.
You could also -maybe- argue that because there's multiple people on the plane (assuming Ol' Muskie isn't flying it himself) and that those people are potentially different every time, without a passenger and crew manifest, it's not identifying individuals (but I suspect you'd not get far with this.)
Planes are very often registered to individuals, and that doesn't even matter! The plane being company owned doesn't magically change anything, what matters is who's being transported and whether or not they will be easily linked to the aircraft.
From a GDPR perspective it also makes no difference whether it's 5% or 90% of planes that are owned by individuals as opposed to by companies.
>edit: Specifically mentioning planes and their locations, I mean, not "extrapolating from cars to planes".
You have to be trolling. What leads you to believe that the GDPR which never mentions either aircraft or cars would treat these two kinds of vehicles differently?
Can you find anything in the GDPR texts to suggest that cars and planes would be treated differently?