What’s interesting is I’d say the same—except for those who became citizens at birth to another country because of being born there.
Weirdly, that apparently was the situation with Cruz and Canada.
I think it's always been the case that American citizenship is not dependent on the rule and traditions of other countries. For instance per the Israeli "Law of Returns" all Jews are citizens of Israel. This has led to many anti-Semites claiming that all Jewish Americans are "dual citizen" with divided loyalty, even if they have never been to Israel or had any interest in the place.
Cruz was a dual citizen at birth. He formally renounced his Canadian citizenship a few years ago. He never renouced his American citizenship.