Remote attestation is the true enemy of your freedom. The power of the authoritarian corporatocracy to force you to use only the (entire) systems they control. It's worth reading https://www.gnu.org/philosophy/right-to-read.en.html again just to see how prescient Stallman was.
I think it’s also worth asking why he didn’t have more impact despite pretty clearly seeing this problem. Part of the answer has to be resource disparities but I don’t think it’s just that - Linux didn’t really capitalize at all on Microsoft’s lost decade, and much of the innovation in security has happened on other platforms. I think there’s also some kind of blind spot in the open source community where a lot of people see this as something other people need, not them personally.
The FSF was strongly against secure boot, then inexplicably started seeming to be in favour of it.
Connect the dots yourself.