> It's surprising not to have seen anyone point out the logical conclusion of a world where every major license includes a React-like stance on patents
The thing is, I agree with your premise that we should always push for licenses that (in the long term) will result in a better free software world where threats such as software patents and draconian copyright are effectively neutralised. All three GPLs did this to copyright (as you noted), and Apache helped step forward on the patent front. I would love to say that the React license helped further this cause. Unfortunately I don't agree, and it's for several reasons.
* This may sound like a minor point, but the React patent license only applies to Facebook's patents, and relies on Facebook retaliating. Code contributed by anyone else may not be giving you the same protection, which means that if they sue someone other than Facebook the target has no real protection. Apache and GPLv3 both tackle this problem because the copyright license is terminated if anyone sues a copyright holder (and GPLv3 even more so because it's copyleft). By only terminating the patent license, you're relying on Facebook suing the offensive party.
* As with almost all patents, Facebook makes it exceptionally explicit that independent discoveries will not be protected. While this is to be expected because it's the default patent law position, it's not exactly what you want if you're going to try to sell me on this being "an ingenious, anti-patent license".
* The patent license clearly favours protecting Facebook over the wider software community. The fact that suits "(i) against Facebook or any of its subsidiaries or corporate affiliates," will result in termination means that the license is incredibly asymmetric in it's protection. The problem is that the "more free" stance of extending this protection to every user of the software would be too strong of a stance for companies to take (it would mean that no company could sue any other over patents in fear of being vulnerable to Facebook's patent portfolio). Not to mention that it still wouldn't solve the patent problem, you'd need to fix my first point and make it apply to all patents by all users. And then it would be seen as an incredibly risky business decision.
* By definition the patent grant cannot be used against Facebook, because of the above protections are not provided. If Facebook sues you over a patent unrelated to React, you cannot counter-sue them for any patents they may be infringing because then you'd be giving them more ammunition. This is where your comparison to the GPL falls flat for me. The GPL does protect users in this situation.
I understand that these might seem like "perfect being the enemy of good", but you have to consider that Facebook's dominant position is what makes these sorts of discussions critical. Sun made some mistakes in the CDDL, and we're still living with those mistakes to this day thanks to the whole Oracle OpenSolaris fiasco (though it went better than we could've hoped). We need to be far more careful in how we evaluate software licenses, and thinking about doomsday scenarios is crucial. If Facebook became a bad actor, would this patent license be better or worse for the community than Apache 2 or GPLv3?