We definitely care about that. Especially since stolen money funds their gulags.

What do you suggest the west do in response that isn't already being done? North Korea is completely isolated in large part due to this.

The big takeaway of the 30 years war was that sovereign nations have the right to deal with their domestic affairs themselves. If you don't like what they do in their own borders with their own citizens you can send them strongly worded letter or refuse to trade with them, but you don't go to war over it. Because that way lies madness (and multi-decade religious wars)

And we are sending NK strongly worded letters and refuse to trade or otherwise engage with them. There is really not much else we can do

But stealing fictional digiBux from Binance is not a domestic affair. You could theoretically go to war with NK over it (though this would obviously be ill-advised for other reasons)

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