The brain operates using electrical signals, and although they are generated biochemically, there’s no reason why they shouldn’t be compatible with computer systems. The key difference is that a computer system uses binary signals, whereas a human brain converts billions upon billions of bioelectrochemical conductions into abstract thoughts and concrete actions every single second. You don’t have to be Musk to realize that there’s a huge technical gap that needs to be surmounted.
Still, thought-controlled prosthetics are a real-life invention, so it’s not unrealistic to think that, eventually, humans and computers could communicate effectively. However, these limbs move with a moderate degree of precision based on a few tens of thousands of electrical neural impulses. The brain involves magnitudes more than this, so at the moment, the technology is relatively primitive.
His latest tweet suggests that he’s “making progress” on the idea, and he may be about to announce something in the next few months. He does have a few more pressing issues to navigate, however, such as the deeply unfortunate SpaceX-related fireball.
There’s a long way to go, then, before this neural lace becomes a reality. In the meantime, Musk is clearly still keeping in touch with his more grounded, Earth-bound side.