Most people donate, but the money will be minimal at best.
Hate to differ with you, but no, I don’t think most people donate. The plasma industry is very successful and Plasma for pay is going to draw a lot more people than donors.
You need good veins and not be on any blood thinners.
It’s been a long time, but it seems like you could find good incentive offers for first time donors. Probably still some colorful people in there with you, too. Only downside would be too-frequent needle pokes in the same area.
I used to donate plasma in college for supplemental beer income. If you are healthy there are no ill effects I know of and it helps people in emergencies. You can’t make a living on it, though.