The section you quite is under this one: >Facebook, Inc. ("Facebook") hereby grants to each recipient of the Software ("you") a perpetual, worldwide, royalty-fr

The section you quite is under this one: >Facebook, Inc. ("Facebook") hereby grants to each recipient of the Software ("you") a perpetual, worldwide, royalty-free, non-exclusive, irrevocable (subject to the termination provision below) license under any Necessary Claims, to make, have made, use, sell, offer to sell, import, and otherwise transfer the Software. For avoidance of doubt, no license is granted under Facebook's rights in any patent claims that are infringed by (i) modifications to the Software made by you or any third party or (ii) the Software in combination with any software or other technology. Emphasis mine. So it seems to terminate just the patent grant. You can't terminate a BSD license so if you're in like France (no software patents) then you are fine to use React and sue Facebook for patent infringement.