David Weber showed why in some of his books. In some of his SF universes, folks had molecular circuitry in their brains - and there were apps that could completely take over your brain through your molycircs!
In another book, Through Stuggle, The Stars, a character had a wireless connection to a computer interface in his brain. He turned it on to access a device, and a captor used this access to crack his encryption. Then they used the link to torture him. Pretty horrible actually. (Great book, too.)
If a future generation puts computer interfaces in their brains, they are going to expose themselves “diseases” beyond their imagination. And the cures might even be worse!
And I don’t even want to think about putting your personality on a computer. The very word “edit” would make you whimper...
Thanks for sharing this with me. Weber’s visionary writings sound more like sci-fi prophetic warnings rather than just fantasy. He has the ability to envision the terrible consequences of the transhumanist quest.