John McAfee decided what we really needed was physical, not software switches in our phones. Makes sense. You want to know the Wi-Fi is off, an analogue switch will ensure it.
There are certainly many technological and ethical considerations when developing brain-machine solutions, but Elon Musk formed Neuralink to explore this next frontier of human evolution. This is worth a read.
The University of Washington has developed a set of 42 playing cards for modeling security and privacy threats. The cards encourage you to brainstorm about potential threats along 4 dimensions:
You may print the cards yourself or request them from the university.