The author of the article clearly had that or something very similar in mind when he wrote this piece. It reads exactly like that story (I had the same thought as you).

It's a very good solution for people who don't know you have something like this. Clearly if the FBI (or whatever) knew of the USB kill device, they'd take a slightly different snatch and grab approach. However if the adversary doesn't think or doesn't know you have something like this, then it can be used to great effect.

Absolutely agreed.

I've read that LEO in the USA specifically try to grab laptops / phones while they are unlocked.

This seems to be designed as a defense against that threat model.

Cases like this in countries that do not have due process laws makes the use-case even more compelling.

If they don’t have due process laws they can throw you in jail until you produce the decryption password, and if they turn on the computer and it’s wiped they’ll throw away the key.

If there is no due process, all bets are off and your best defense is to be uninteresting to authorities.

Things are not always black and / or white. The rule of law, in reality, is rather a continuous variable then a binary one.

And even if: A kill switch can simply hide / erase some things and present some weak evidence..