[Vespasian]

There are tons of rules around these kind of robots in regular work environments for precisely this reason.

Usually there need to be either a physical barrier like a cage or a virtual one like a laser waterfall that detects foreign objects in the robots perimeter and emergency stops it.

These rules were disregarded here.

I used to work in a company were such machines were developed and even a very experienced engineer, working on a prototype, was once hit by it (no serious injuries and safety was improved afterwards) because they can move very fast and in unexpected ways.

These days there are better solutions available (so called cobots) which are designed to be work together in very close proximity with humans whiteout physical separation. They feature very sensitive force sensors and are severely restricted in the way the are allowed to move.

So yes "think of the humans/children" does apply here. This is a solved problems and the operators decided to disregard established procedures and went instead for "flashy and cheap" (cobots are more expensive and slow as molasses)