If you trust your government, you can already voluntarily pay taxes even without automatic taxation feature built into blockchain.
But let's leave a choice to trust, or not to trust, up to the people.
It is up to the people. Why? There is nothing in law or codes that ties you to the IRS or taxation, if you don't want to be. Your name isn't in the codes, or even the law, is it? Then how can it apply to you?
The reason why people lose against the IRS in court is, they are tricked into admitting their guilt. But they don't have to for several reasons. One reason is, a person's name is not in the IRS code. So, taxation doesn't apply to him. The way it is made to apply has to do with the person agreeing by signing a tax form, or by being tricked in court.
Youtube search on "Karl Lentz common law" to find out how to keep the courts from applying taxes to you. If enough of us do this, and win at court, taxes will clearly and easily become voluntary.