If the car might be safe, but you are not sure yet. So you have someone monitor until the confidence level allows unmonitored operation.
Like student drivers: passenger can't do anything but evaluate and yell. Or Tesla with nags (on a better future SW version)
Then they need to be in the car. There's no way a remote system over internet can be safe for realtime control on this level. Ping over 4g can also be terrible further increasing lagency6