The main problem they don't talk much about, and why this isn't ready to go mainstream, is that those brain implants will decay over time.

The brain will build up scar tissue around the electrodes and render them useless. These are basically little needles put into a jell-o which then wiggles around all the time. This constantly irritates and damages the tissue. Your immune system hates this.

Even within months there's a significant decay. But, within 5-10 years most of the array becomes pretty useless. Of course, you can't replace it easily. And the damage to that area, while local, isn't reversible.

There's a lot of research on trying to make a brain implant that can last longer so that all of these treatments become viable. But we still have basically nothing.