Donating blood/plasma is a good thing. Economic conditions in which poor people feel obligated to give blood just to make enough money, whilst rich people don’t feel this same pressure, are bad.
I don’t know how exactly private blood banks work (in plenty of countries blood banks are public and presumably non-profit), but regardless, I assume nobody can get blood transfusions if nobody donates. So until the political system is overhauled just keep donating? Your blood donations aren’t the root cause of capitalism
No, there is simply no such thing as “zeroth”, that’s not how ordinal numbers work. If I have the following numbered list:
Foo
Bar
Baz
The first item is “Foo” which is indexed 5. It is not the fifth item, because the item indexed 5 comes first in the list, so the item indexed 5 is the first item. Ordinal numbers don’t refer to index, they refer to order.