> I'm more confident that local apps on my Linux desktop are secure

Why should you be? Linux gives us software we can reasonably say we own, but not hardware. Everything you type into your local linux apps can be being monitored by your processor and whatever is sitting in the CSME/PSP subsystem which you don't have permission to access, but which is always running even when your computer is off. We need fully open, documented, auditable hardware if allowing any third party access to our devices means our private documents will make us all into criminal suspects.