The article mentions embarrassing photos, for example, that you might value but not want someone else to have.

While not a safe, there are tamper-resistant computers that are embedded in safe-like enclosures. Some of them have explosives to make sure even things like RAM chips can't be recovered if they sense tampering. [1]

I've worked in the civilian wing of a company that did this stuff. What I dealt with just enough power to wipe crypto keys if they sensed things like a tilt, air pressure change, or power loss. I'm sure the military side of the company had fun things to deal with.

[1] https://www.cl.cam.ac.uk/~rja14/Papers/SE-14.pdf

TFA mentions ‘ canisters of tear gas hidden behind a safe’s inner-door plate’. That definitely sounds like an anti-tampering device. If they were simply stored inside the safe, the article would have said that, and the cracker wouldn’t have nearly drilled into them.