You assume more than what I suggest. I am in favor of proof of citizenship issued by your state in the form of a birth certificate, but a SSN has no influence over that. I also recommend you get them a state issued ID card so they have two forms of ID required for almost anything (if youre a legal citizen). There is a form you can fill out for them before they are of age that enables this, and it is more difficult after they are 18. One can live off of bitcoin today, its not that difficult, it can be done. To not get your a child a SSN is not bearing a burden on them, they can sign up for it any time. The burden is on YOU to inform them how to take advantage of their freedom.