Ouch, harsh, but true. It’s kind of insane how much is out of our control nowadays, and how companies don’t seem inclined to do much of anything about it. I hear that AMD at least, is going to switch to an open source alternative to PSP in the future though.
We’ll have better open source hardware eventually. Today’s fpgas, at least the affordable ones, aren’t quite powerful enough to make something as performant as a modern motherboard but we’ll get there eventually. People are already working on homebrewed x86 stuff which is going to set the groundwork for 20 years from now when every single computer not made in a hobbiest’s garage is as locked down as a modern iPhone.
You may want to closely monitor developments around RISC-V and ARM CPUs if security is a top priority in your Linux hardening efforts. It’s crucial to remember that maintaining security extends beyond just your computer—it’s a multi-layered process.