Sounds like Fedora is sacrificing good code for ideological purity.
> Part of the background story is that on patents, we've fought the scenario that a patent holder could offer some FOSS library implementing their patented method, and then come chase you for patent infringement. What are the boundaries for me, FOSS user, to not be ensnared by a submarine license?
Honest question: How could they claim damages from someone to whom they've granted permission? It just doesn't seem like a likely problem. So i'm trying to understand what the actual threat is.
That's actually the underlying rationale here, although it isn't explained well in the linked page. There is the possibility of an implied patent license grant (or waiver) from the licensor in a license that is silent about patent rights, for exactly the reason you state.
But CC0 is different, in that it grants permission to use while simultaneously being explicit that there is no implied patent license (or waiver) granted.
I think that's the key: technically they haven't granted permission, not explicitly, absent a patent waiver. (Disclaimer: not a lawyer, barely paying attention to this.)