I know, and they can be hacked too through sms messages.
But the sim card doesn't have access to the car telemetry. Probably even the whole baseband module doesn't. It just gets that data to transmit when an accident happens.
The worst you could do by hacking the SIM is to make the modem send nearby cell data somewhere. Which is serious enough because the rough location can be derived from it. But it's a far cry from what these manufacturers collect.
But the sim card doesn't have access to the car telemetry. Probably even the whole baseband module doesn't. It just gets that data to transmit when an accident happens.
The worst you could do by hacking the SIM is to make the modem send nearby cell data somewhere. Which is serious enough because the rough location can be derived from it. But it's a far cry from what these manufacturers collect.