Seems to be significantly more equitable than the React license that people were originally concerned about. That one terminated your rights to use React if you sued Facebook for patent infringement for any reason. This one only terminates your rights to use Go if you assert that Go itself infringes on your patents.
That also sounds pretty reasonable. You don't get to patent something, contribute code that uses the patent to go, and then sue people using go for violating the patent.
