Also wildly illegal to use to conduct government business, especially confidential government business. (and yes the messages were auto-deleting and largely lost before anyone chimes in with technically they could be archived!)

It was a custom (presumably DoD-approved) build. But the story gets much better than that:

https://youtu.be/KFYyfrTIPQY&t=724

Ok? Signal is not the topic of my comment really, nor has anyone claimed it's less secure than other chat apps.

> Signal is one of the most secure communication platforms out there

That might be true amongst the communication platforms available for the average Joe. It is definietly not the most secure communication platform available for someone high ranking in the USA government.

> it is obviously not immune to human error or social engineering

Nothing is immune. But there are systems more and systems less prone to these issues.