It seems unlikely they put the same efforts into finding a zero day for a nokia. There might be a super easy to find zero-day though, like you're saying.
If it's anything like the old days, they don't need to horde a 0 day.
There were always obscure pieces of software that would pull your forgotten pin right off the device with the right secret code, in which case you have full access to the device.
I'd also expect them to be vulnerable to much simpler attacks like just reading flash chips directly
> On the other hand, China is known to have and use ios zero days
What's your threat-model? If your adversary is a nation-state on par with China, you're probably toast unless you have a well-resourced entity supporting you (think large corporate or another nation-state)
It seems unlikely they put the same efforts into finding a zero day for a nokia. There might be a super easy to find zero-day though, like you're saying.