Earlier quoted context omitted.
I'm aware of the strange views of Libertarians, but I'd never heard a currency itself marked as coercive! I agree: It's a strange view of coercion where getting fired and ending up on the street provided you're fired by a private employer is less a coercive act than having to pay a percentage of your income for social benefit, or, worse yet it seems, having to use a 'coercive currency'.
Protection from being fired comes with a cost. Less people are willing to open companies and easily hire people to do job if they are afraid that they wouldn't be able to fire inefficient workers. All "unemployment" is government creation due to either "free" stuff like unemployment benefits or to regulations that prohibit some employers from hiring you.
On your first point, it's not whether or not it comes with a cost that is the relevant question. The relevant question is: If it does come with a cost, does the cost justify the benefits and/or are we willing to pay the cost?