Funny thing is that we already live in a world where theoretically no one should be accountable for what "their" devices are doing. How the eff am I supposed to

Funny thing is that we already live in a world where theoretically no one should be accountable for what "their" devices are doing. How the eff am I supposed to know which messages my phone is sending? From hardware vendors over operating system vendors to messaging app vendors and potentially even the mobile network provider, there's a shitton of people that could be messing around with my phone already. The price for a targeted attack might still be significant, but it's not prohibitive for many scenarios. So why would the content even be interesting for any law-enforcement agency?