Congress already passed a law to prevent foreign libel judgements (well, ones which wouldn't pass 1st amendment muster), from being enforceable by US courts.
And now we just have US judges deciding they should apply NZ law without applying the 1st Amendment?
I think maybe this is because the user who left the review is a New Zealand national residing outside the U.S., so they do not have any first amendment rights. If the user was American, I think they could assert a first-amendment right to anonymous speech to prevent being identified. (Although such a right is not absolute, there is a balancing test involved: https://storage.courtlistener.com/recap/gov.uscourts.cand.36...)
And now we just have US judges deciding they should apply NZ law without applying the 1st Amendment?
https://en.wikipedia.org/wiki/SPEECH_Act?wprov=sfla1