I've never worked on artificial knees. My frame of reference is artificial hearts and surgical robotics, those are on the same order of complexity as Neuralink, so my experience is pertinent IMO.
I'd argue that the brain and the heart are at least 2 orders of complexity apart. Granted many neurologists try to treat the brain as if they were similar, and current brain implants essentially function as pacemakers, but I think most folks that are excited about Neuralink are excited because for the first time they are building interfaces that begin to cross those 2 orders of complexity.
We are not talking about those though. We are talking about devices that treat the brain and heart, completely different. Devices that treat the heart are far more complex devices - they have moving parts that need to work seamlessly while submerged in blood. Brain implants are just glorified PCBs in enclosures with electrodes. No moving parts, no motors.
It's also not the first time those things have crossed. We've been doing cochlear implants for decades, neurostim devices for nearly as long. None of this is new (except for the Musk being an ass part)
