Comment by Banana699

The thing you're missing is that BCIs and friends are, themselves, computers, and thus securable with post-quantum cryptography, or any cryptography for that matter, or any means of securing a computer. And thus, for somebody to read-write to your computers, they need to read-write to your brain(s), but to read-write to your brain(s), they need to read-write to the computers implanted in your brain(s). It's a security cycle whose overall power is determined by the least-secure element in the chain.

Any sane person will also not touch BCIs and similar technology with a 100 lightyear pole unless the designing company reveals every single fucking silicon atom in the hardware design and every single fucking bit in the software stack at every level of abstraction, and ships the device with several redundant watchdogs and deadmen timers around it that can safely kill or faraday-cage the implant on user-defined events or manually.

Alas, humans are very rarely sane, and I come to the era of bio hacking (in all senses of the word) with low expectations.