Yes but at some point combustion engine cars will probably be banned.

Perhaps, but by the time this happens, I'll probably have died of old age. And if it happens sooner, then I expect that there will be electric cars that, either as designed or through aftermarket modifications, won't phone home.

And if that doesn't happen, then I guess I won't be using a car. Which is probably the best idea in terms of environmental impact, anyway.

Just snip the LTE antenna in a Tesla and you have an offline car. I can't claim to know if Tesla has built in any actively hostile features like the car going into a maintenance required mode if it's been too long since a ping home, but I do know that the car is fully operational without connectivity (not including features that required connectivity, like navigation data, of course). There are even physical RFID keys.

That would count as the "aftermarket modification" I mentioned.

Not banned, but gas will become too expensive to operate them except in special circumstances. Once we start factoring in the cost to recapture the carbon emitted from combustion engines they will be instantly uneconomical.