With a few exceptions (like serving alcohol) Amtrak doesn't care much if a state makes a rule, since they are not bound by them, but the Federal Gov't will not make it mandatory, The states that choose not to allow gov't participation with them might be able to do it for their own state agencies, but prohibiting use by private entities like the Clown Prince of Posturing is doing in Florida will most likely lose as soon as it hits the courts. Pretty hard to make a case that gov't should not impose strict guidelines on what private businesses can do, they should be free to make their own choice, like capacity and masking mandates, and then say except you can't do this.