Well, the first problem is that these things cause cancer.
It is why you didn't hear about this technology for a long while.
It was all the talk back in the 80s

"Modern Medicine" doesn't know shit about the brain.
They are still thinking that the brain is where thought happens.
I mean, really, there are more neurons in the gut.
But, that doesn't matter, because neurons are just a connector to higher dimensions.

"Modern Science" doesn't know shit about the brain.
One researcher was caught by another using a sharpy on a graph of the data he was about to show the forum. "He was actually marking out the signal, thinking it just noise"

"Modern Biology" doesn't know shit about DNA.
Not one is talking about how DNA is, both, a perfect magnetic antenna and an electrical antenna.
They were still calling parts of DNA junk, (just a few years ago) because they couldn't figure out if it did anything.

Given all of this, we will get a neuralink by two methods.

1. Blind chance, luck and engineering.
2. Its alien technology, or ancient earth technology, and Musk is just the one who T.H.E.Y. are introducing it to us through.