Earlier quoted context omitted.
Old way: you repeat the measurement nothing is in your body. and you konw di you feel e.g. hypo. New way: the sensor needle is simply a little off (in stays sticked). You don’t know, the software doesn’t know. The sensor is not magic that works 100% of the time, it ends in a needle sticked in your body, many ways to go wrong, even if it worked a while. And the danger of “fully automatic” is there.
Just to clarify, we were only discussing monitoring and sensors in this subthread. Not closed loop pump systems. A sensor failure in closed loop is dangerous. I do not know how the control software detects and deals with this. I have no experience with them.
The sensors are big things with the needle permanently in your body. You don't want three needles permanently to be sure that at least 2 from 3 work. If you have only one, you have a real problem if you trust it blindly.
Yes, it's good that some people try. But there are real risks, due to the current limitations as explained.