Reserving judgement until more details. It sounds like she definitely did do something wrong, eg leaving a child for at least 10 mins in a hot car, but despite the 'more than an hour' headlines, all that is known is that she parked an hour earlier, we don't know if she might have put the toddler in the car just before it was noticed.
As I said, even if it was 10 minutes, that was the wrong thing to do, especially without any ventilation. But we know nothing else about her as a parent or what happened that day, so I am loathe to start labelling her negligent or cruel or even stupid. She might just have fucked up collossaly while exhausted and at the end of her teather, and otherwise be a great parent. I'm not going to judge a parent on one thing (unless it is blatant cruelty) without all the context.