Apples and oranges. The vote is a foundational right. Not an obligation. Democracy by definition can't be forced onto you. Voting is definitive of democracy. Requiring someone to get a drivers license should they choose to drive a car is just transit policy. Not at all comparable.
I like the earlier idea. Give people a "decline to participate" box on their ballot. Still puts a ballot in everyone's hands, but doesn't put a gun to anyone's head.