Conservation of momentum doesn’t mean that the momentum of the emitted photon has to be equal to that of the absorbed photon. It means the sum of the momentum of the emitted photon and the mirror must equal the momentum of the absorbed photon, assuming the mirror had no momentum to begin with.
I'm pretty sure when Decartes said that, he meant that that's the only thing we know for sure to be true, since everything else could be a hallucination. He wasn't making an argument for cognitive enhancement... was he?
To be fair I quite like that feature. Usually if I'm disconnecting from a WiFi it's because it's not working very well and I want to use my mobile data instead. If I forget to turn it back on I'd end up using way too much data.
As I understand it, they tried to design a new plane that wouldn't require pilots to be re-trained on how to use it, if they'd already been trained on an older model. That's the UX I'm referring to.