Then you have no patent protection in the first place! You are in the same situation as when the patent grant expired because you sued them. I don't see how this is any better.
You do not give them a license to use any patent. You are right that in practice the non-enforcement means that they can willy-nilly use your patents. But if we are arguing about factual ability vs legal rights - they can probably already to that, due to the fact that they likely have more money and better lawyers then you do.
And if you do have the license - then what? It's still a react death-knell should any submarine patent appear; no large company is every going to agree to such an assymetrical deal.
Better to at least be left in the situation where it's likely in facebook's own interest to never surface any (so restrictively licensed) patents in the first place.
The thing is, if you just use react for something inconsequential, and can live with the fact that you have to cease using it when you sue Facebook, then it is fine.
You shouldn't base your business on Facebook's (potential) patents, and then attack them with your own patents - but that is true with or without the patent grant.
Of course, what would be great would be 1) a finer grained, symmetrical patent grant, or 2) a bilateral agreement between your company and Facebook instead of the patent grant. If you are big enough and have patents, you can probably negotiate something like that.
The chilling future effect, which I believe is the primary driver of op worries, is what if you build on React and are the next Facebook? (I.e. you are growing quickly to become "big enough" but are not yet)
Old Facebook now how a lot more leverage on you at several critical moments -- either in terms of making an offer, or in the negotiations around a more reciprocal patent licensing deal, or the aforementioned infringing of your patents, or the mere threat of either if someone else makes an offer.
The entire point of ladder kicking is to build a moat to ensure that others can't grow past you in the same way you did, and this is pretty effective at that (intentionally or unintentionally).
As you said, a more reciprocal, more finely-scoped patent balance would resolve these concerns. (E.g. "if you sue Facebook over a patent involved in React...")
If Facebook wanted to be the good guys here they would license under Apache 2.0 or write their own symmetric patent grant. They already relicensed RocksDB after Apache's move, perhaps they will do the rest of their stuff too.
Not really. If you have BSD with no patent grants you can at least argue that there's an implicit patent grant. If there's an explicit patent grant which you violated/got terminated that defence is clearly not going to fly.
I was involved with an opensource project which got a patent application submitted by the company. Even though I pointed out prior art. And even though I refused to sign the application as one of the authors. That's corporate environment for you.
If Zuckerberg signs a paper with the wrong title, there's a troll lawsuit the next day. So if you make a habit of "in practice" strongarming people, you can easily slip up and have a huge headache on your hands.