One of the first questions I would ask is what is an indirect assertion of a patent in this situation? If you get shaken down by a patent troll for a patent related to React stuff, would that be considered an indirect assertion? After all, you're making a statement there that React is violating some patent. While I can agree with patent severance clauses, this one just feels full of real ugliness that would drive a lawyer crazy.

Maybe if your company's very small, but if your company is large enough, you almost certainly will have patents.