We should understand that the alternative is very imprecise: poking yourself and trying to time the right delivery of insulin doses, based on your current blood sugar, exercise levels, meals, etc. It's a guessing game with diabetics, so this is a giant leap forward in making them healthier, even if the tech wasn't 100% perfect.

My dad had been lethargic as he ages, the doctors just told him that the level he was maintaining his blood sugar at was much lower than he should be at for his age. They also gave him an in-arm blood sugar reader. The difference from these small changes has been enormous. He seems more alert and healthier than he has in the last couple of years and he keeps more on top of the sugar levels with the new reader. My point here is that people risk their own lives trying to manage their own blood sugar, and even the smallest tech add, like a device that suggests the right insulin dose can be life altering. Diabetics who fail to manage their blood sugar properly can lose limbs and go blind. Given the choice of going it alone or using a technology used by many others, I know what I'd choose.

    insulin_dose(blood_glucose, activity, carbohydrate, fat, protein, time_of_day, time_of_month, is_saturn_in_retrograde, **kwargs)

Practically, in the discussed system the pumps themselves have built-in maximum boluses so the control-loop is limited in how badly it can fuck up. Of course, you have to trust the pump firmware...

That said, I've done some pretty stupid shit. Like the time I injected a huge bolus of novorapid, thinking I was doing my Lantus shot. Ugh.

Like, software can have failsafes and error handling, but at some point any healthcare product may require user intervention.