He is using the concept of legal free speech correctly while memeing about a philosophical free speech that matches the colloquialism that many of his sycophants and observers think

Legal free speech has only to do with retribution via criminal liability from government organizations, alongside freedom to disassociate from speech and expression that you don't like

Twitter is not a government organization and is also not capable of levying criminal charges against anyone, and is free to disassociate from speech and expression it doesn't like thanks to the 1st amendment. Yes, this is the same capability as anyone else and the same possibility as Twitter operated before, aside from different choices of who its leadership chooses to dis/associate with.

It is an accurate commitment to free speech.