And it also just opens the possibility for centralized ID verification services being breached and tieing identities to their more personal vices, its only a matter of time till a ID services gets exploited and a bunch of peoples identities and the sites they use are exploited.
In general any legal argument of the form: People will break the law, so there is no point in the law, is bullshit. Imagine any law and you will see how ridiculous it is.
"Making stealing with guns is illegal, people will use facemasks and file gun identifiers" "Adding security features to money is pointless, counterfeiters can always " "Adding locks to doors is pointless, if an thief wants to they will picklock it or copy your key" "making alcohol illegal is pointless, kids can present fake ids or ask their parents..." murder illegal is pointless
EDIT: And by comparison, most societies get along fine with very limited access to firearms. Only the most repressive manage to enforce bans on unpermitted forms of drugs or sex.