Earlier quoted context omitted.
I guess it depends on whether it would be easier to create life support systems for human workers or build robots for the job. As for what makes us human, I'd draw the line at "individual thought", but even that's iffy. Fully electromechanical/robotic bodies, for example, would be strange but people would still recognize you for who you are. But if we're joined in a hive mind with shared memories/thoughts/etc, I thin…
Personality changes as described don't really matter IMO, because broken . Regardless if machine or man. Does not work as intended anymore, or at all.
People that go through depression, suicide thoughts/attempts and then recover are also different, because they gained new information.