In American law, the right to speak is assumed. It is the lack of a right to speech that is the exception. There are only a handful of categories of unprotected speech, which can be easily enumerated, and lies aren't one of them.

Fraud, defamation, perjury, and obstruction of justice are illegal. That's a much narrower restriction than a ban on lies.

Agreed there is no explicitly enumerated right, but in the context of computing, it is not illegal for a computer to transmit “untrue” information. Fraud is a significantly higher bar. I am not a cyber-lawyer.

You cannot keep me from lying. You can only hold me accountable if my lies do harm. So I would take it as a "natural right" even though I realize those are contended.