This sounds straight like future-future-tech. My Fitbit can't even measure my heartbeat or steps with sufficient precision and they want to measure electric signals from neurons? Sounds (yet) impossible.
There have been commercialized versions of this tech already. The Myo was Kickstarted in 2015 and then acquired by CTRL-Labs. I have one and that generation of the tech was still tricky to use effectively.
https://www.kickstarter.com/projects/312488939/myowaretm-har...
Here's a pretty decent paper on the quite long history of Brain-Machine Interfaces: https://www.physiology.org/doi/full/10.1152/physrev.00027.20...