This data is the equivalent of tracking all the data off the mobile phone of an unknown person -- it is anonymous but trivially identifiable. The data is also definitely copyrightable in nature, being complex engineering analytics customized for the vehicle by the manufacturer and used for a wide variety of internal purposes. The contents and semantics of this data varies widely across manufacturers. It goes far beyond dumb telemetry.
Much of this data is treated as a legitimate trade secret by the manufacturer and is generally deemed to be owned by the manufacturer for legal purposes, though they are sometimes required to share it with regulatory bodies. Automotive companies would strongly object to this data becoming public because it would adversely impact their ability to maintain a technological competitive advantage. That their engineering trade secrets are covered under GDPR makes it that much more awkward, but owning a copyright on this data at least gives them legal standing to enforce compliance. I've worked with major European automotive OEMs -- they would lose their minds if you told them this data is no longer theirs to control.
Much of this data is treated as a legitimate trade secret by the manufacturer and is generally deemed to be owned by the manufacturer for legal purposes, though they are sometimes required to share it with regulatory bodies. Automotive companies would strongly object to this data becoming public because it would adversely impact their ability to maintain a technological competitive advantage. That their engineering trade secrets are covered under GDPR makes it that much more awkward, but owning a copyright on this data at least gives them legal standing to enforce compliance. I've worked with major European automotive OEMs -- they would lose their minds if you told them this data is no longer theirs to control.