Greetings from Ukraine, European country with real Great war just now.
I must say, we see extreme grow of cyber-crime as part of modern war. I think, in nearest future, cold war will guaranteed have huge cyber-crime part.
And, hacking of IoT devices has very significant share of cyber-crime now. For real war it is question of life and death, because hacked devices with radio emission, are used by hostile intelligence, to find targets for attacks of heavy weapon, but also, we seen cyber attacks on electric-energy infrastructure, indented to make blackout (fortunately for us, unsuccessful).
Chinese IoT devices are very special part of question, in many cases are connected to Chinese clouds, and this is also extremely dangerous, not only because potential unfriendly Chinese moves, but also because their security is not good enough, so in many cases, cyber-crime could intercept communications and interfere operation of device or even hijack control.
For example, exists smart door locks with camera and I hear hackers hacked them and used them to observe work of air defense, so enemy could tune their air attacks to make more harm.
In civilian life without war, videos from hacked door locks (or other IoT cameras) could be used for illegal surveillance, to coordinate riots, etc.