Okay, how is that inherently useful? All any form of trusted boot does is make sure, that the OS is whatever the manufacturer approves. If that is an outdated image full of backdoors and exploits, than that is what the TB enforces. TECHNICALLY a phone on android 2 is secure because the TB enforces that awfully outdated image. All trusted boot is good for is to make sure you can’t run acutally secure software on your device