I read it's because the FAA has a list of flights that cannot be displayed on sites like that, called LADD: https://www.faa.gov/pilots/ladd
> The Administrator shall, upon request of a private aircraft owner or operator, block the registration number of the aircraft from any public dissemination or display, except in data made available to a Government agency, for the noncommercial flights of the owner or operator.
Thus the only public source is ADSBExchange because it uses croudsourced data. Imagine that people put crowdsourced license place readers on their private property and then through a made an aggregate of this data on the public movements over every car available (and charged commercial users.)
That would be quite problematic for personal privacy.
ADSBExchange isn't quite the same as that since airplane movement is less granular and thus less privacy is lost. Also, the people who use private jets tend to be rich and powerful, so there's an aspect of "punching up" here that is not present in the crowdsourced car movement analogy. Still, I don't think the privacy considerations here are as cut and dry as the people who are claiming "it's public data, what's the problem?" are making it out to be.
I am certain that I believe that selling or providing aggregated location data on my movements (edit: via tracking my phone or vehicle) should be illegal.
I am less certain about if I feel the same way about plane movements. I do believe that is a discussion we should have rather than just assuming thr loss of privacy is worth the transparency.
Honestly, why would anyone really care where his jet goes unless you are him, his crew, or ATC?
The only reason folks would be obsessed with this is for nefarious reasons or just out of a blatant disrespect for the privacy of another person. Only negative reasons.
