Evil comes in many ways. This can be argued is just massive negligence and ignorance, or even arrogance. As a father, when all this topic is paired with babies, I don't mind calling it evil and treat it as such.

If the 1000 lives were not in imminent danger or else could have been saved by other means, it's not trivially true that only killing 1 in 1000 should be neglected. How does that compare to the alternative methods? Could it have been avoided with small or reasonable changes to the product? Were people properly informed of the risks? There's a bunch of stuff to unpack here. It's not trivially and obviously true that it's A Bad Thing to get sued if you save 1000 lives and kill 1.

On the other hand, if you are in the situation where those 1000 people are absolutely going to die imminently, your product has the only possible chance of saving them, and in the end 1 person dies sooner than they would have without treatment... you're not going to see a major and massive lawsuit out of this. You can be sued, but your annoying neighbor can also sue you for being annoying if they want. Doesn't mean it'll go anywhere, or that you'll lose your pants from it.