> A 2016 study in the Economic Journal finds that the immobiliser lowered the overall rate of car theft by about 40% between 1995 and 2008.
Getting it stolen renders you "not allowed to drive it" pretty effectively, and it's a lot more likely than your immobilizer malfunctioning. If you don't drive a Hyundai, Kia, or a 30 year old car, chances are your car already has one.
1: https://www.aclu.org/news/privacy-technology/congressional-d...
Also, the immobilizers in question don't "phone home", they just require a key that's been paired with the car. (Granted, if you lose all the keys, it's a pain. You need a mechanic with a computer to reset the ECU and pair new keys.)
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https://support.lenovo.com/us/en/solutions/ht105220-unintend...