[ue_]

This sounds horrible, even though I knew about it before. What are the viable options for other manufacturers or architectures which don't come with this sort of thing, either for desktops or for laptops?

[chx]

So the mainstream is Intel and AMD. Both are out.

https://libreboot.org/faq.html#intel https://libreboot.org/faq.html#amd

See https://libreboot.org/faq.html#whatcaniuse -- your best bet is older Intel / AMD.

There are some laptops https://www.crowdsupply.com/sutajio-kosagi/novena which are open.