basis

https://en.wikipedia.org/wiki/Hanlons_razor

"Never attribute to malice that which is adequately explained by stupidity."

This is a... variation / argument for in dubio pro reo, which is pretty foundational to our legal system.

I'm seeing it being used to defend the powerful and the mighty, which is wrong.

"Anything that can go wrong will go wrong."

Is known as Murphy's law.

There is a very simple choice:

• Either we treat people, everyone, as conscious, knowing, somewhat enlightened people, who are aware and responsible for their actions and predicting the outcome of their actions and who have the responsibility of taking care of their fellow humans.
• Or we don't, which would eliminate the concept of personal accountability.

arguments

It is the responsibility of those wiedling big structures, lots of resources and decision power to take appropriate care when doing so.

The definition of "accident" hinges on the amount of precaution that can be reasonably accomplished by actors. For average individuals, the amount of resources they can spend on prevention or precaution is limited. We still ask for responsible behavior, but "accidents happen".

For governments, big corporations or other big organizations, the concept of "unpredictable" or "unforseeable" or "unpreventable" ceases to hold meaning. Their nature affords them with quasi infinite resources. It enables them to take into account the most remote of possibilities and achieve "complete oversight" over the subject, as long as it's under their control. An accident in this case, isn't an accident.

It is a pre-planned lack of attention to detail. They didn't cause the accident, but they purposefully disregarded building the infrastructure for prevention, when they could have and it is part of their responsibility and they had the resources to do it.

We can argue about grey areas, where something was "unpredictable" or not. But when looking at the extremes, toddlers aren't responsible, because they are "stupid". The leader of multinationals or countries are not "stupid". They can't be, by definition. If they are, it means there is a large groups of idiots who have not noticed their stupidity and not opposed putting someone stupid into a position of dangerous power. This doesn't excuse the bad outcome, it extends the responsibility for the bad outcome to that large group.