But from my imperfect understanding if you own the technology/product, not if you just use it. So Facebook may sunset React Native? But I'm no native speaker.
Native speaker here. You're correct. "Sunsetting" is when the creator slowly phases out manufacturing / support for a product, so FB would need to be the one sunsetting React Native. AirBnB should say they're "transitioning away from" React Native.
The extra connotation here is that AirBnB was perhaps the most visible/vocal user/proponent of RN after Facebook. They built an entire engineering org on it, etc.