(Scrolling down the comments, I am honestly disappointed that I am the only person asking this question. Or does everyone else already know and I'm just out of touch?)
Sadly I think assuming a new x86-based system could possibly be "truly open" if it isn't a screaming headline-feature is kind of out of touch, yes.
AMD to consider coreboot/Libreboot support for Ryzen [1]
Although, the only Framework with Coreboot support is their Chromebook, which has to use Coreboot per Google. But, comments in this thread seem to indicate broader use of Coreboot may be possible from Framework, in the future [2]
[1] https://news.ycombinator.com/item?id=13781408
[2]https://community.frame.work/t/coreboot-on-the-framework-lap...