On the M1 and M3 subway of Milano, even if they operate in ATO, the driver is absolutely responsible for the train. ATO or not ATO, Goa1 or Goa2, the driver is fully responsible for his assigned train.
On a high-speed train, ATO or manual you can not do much to avoid an obstacle, but do not even pretend anything, you need to mitigate as much as possible an impact, use the GSM-R alarm and make a series of planned interventions. Most high-speed trains use instrumental systems (TVM-LZB-ETCS etc.) that do not need to look outside, but the driver can not drive with the curtain down on the windshield. Also there are other unplanned contingencies ...
For example, a long time ago, on the M3 of Milano, a slowdown was installed for a flooded track, of 20 mph, not managed by block programming, so in the first station a driver-tutor goes on board to make the slowing down manually, because the drivers no longer knew how to drive in manual mode, exception of the shunting, after the slowdown, the driver-tutor gets off the train and goes on board the other train to make the slow down in other direction . Or I can tell people invested because they fell on the tracks without the driver noticing, because he looked at his smartphone. So, if you want to commit suicide ... throw yourself on the M1 or M3 of Milan, guaranteed death.
The DLR is a slightly different system, similar to an automatic subway, with a simple management. DTO and UTO have a very different management of an ATO, they must have many more things: sensors, cameras, real-time alerts to the control room on all the characteristics of the trains (voltage, engine failures, temperature axes etc.), you do not have need to maintain driving skills because in case of system failures in DTOs proceed at low speed to the first station in order to free the track (a simulator is sufficient to guarantee a minimum of driving skills), do not even have a signaling or another way of guaranteeing full service with an operator all the time, because they are very different lines from those GoA1 and Goa2 where if the ATO does not work then you can continue to drive manually. On DTO and UTO if the automatic driving does not work you can only free the track up to the first station, there is no ordinary service with the driver that drives, even the train dashboard is very simplified, without too much information, quite different instead dashboard of an ordinary train (ATO or not ATO).
With this I do not want to say that in the future also the main line will not be DTO or UTO (this I think improbable), I just want to say that ATO-DTO-UTO are not the same thing, especially in the main line is very difficult, but not impossible.