I did a PhD in brain-computer interfaces, including EEG and implanted electrodes. BCI research to a big extent focuses on helping paralyzed individuals regain communication.
Unfortunately, EEG doesn’t provide sufficient signal-to-noise ratio to support good communication speeds outside of the lab with Faraday cages and days/weeks of de-noising including removing eye-movement artifacts in the recordings. This is a physical limit due to attenuation of brain’s electrical fields outside of the skull, which is hard to overcome. For example, all commercial “mind-reading” toys are actually working based off head and eye muscle signals.
Implanted electrodes provide better signal but are many iterations away from becoming viable commercially. Signal degrades over months as the brain builds scar tissue around electrodes and the brain surgery is obviously pretty dangerous. Iteration cycles are very slow because of the need for government approval for testing in humans (for a good reason).
If I wanted to help a paralyzed friend, who could only move his/her eyes, I would definitely focus on the eye-tracking tech. It hands-down beat all BCIs I’ve heard of.