That's an interesting hypothetical, but there's no way someone could donate blood "full time" to earn a living wage. There's an upper bound to how fast one can produce blood, and a high proportion of people are capable of doing it, so each person can represent at most a miniscule proportion of total supply. It would be like making a career out of football if almost everyone were equally fit and talented and lots of people played all the time for fun and there were no NFL.
But what if we could we increase the amount of blood someone can donate. I know something roughly similar is done when donating marrow.
What if we could augment humans to be able to produce absurd amounts of blood and make it so it was a full-time job for those people?
If we could increase the amount of blood someone could donate by 100x, would it start to become cheaper to just hire full-time donors rather than deal with all the expenses around donations? And would it be ethical even if the donors we're fully consenting and paid a good salary?
Like you said, its a interesting hypothetical to say the least!
