Based on the precedents of Barry Goldwater, George Romney, John McCain, and Barack Obama, yes he is. To hold Cruz to a different standard would be an arbitrary and capricious application of the law.
SCOTUS will defer to the Electoral College on the issue. Obama's election and re-election is proof of that.
What is Ted, the NBC of three countries?
That's theoretically possible. For example, under Panama's constitution, John McCain was an NBC there too when born on a U.S. military base in Panama. He was also a U.S. NBC.
When a dual citizen minor becomes an adult, he is supposed to choose one citizenship over the other (assuming he knows about it). In practice, that rarely happens.
For example many dual NBCs (particularly U.S.-Canadian) keep both. It's only been with the implementation of the U.S. Foreign Account Tax Compliance Act (FATCA) reporting requirements that you're seeing a trend by dual NBCs living in Canada to renounce their U.S. citizenship as adults.
It's not arbitray and capricious if the analysis yields the same reult in each case. That the precedents err is a fact. Goldwater at least can claim he was born a citizen of a terriroty that later became a state, and Mccain has an argument that he was born a citizen of whatever state his parents were domiciled in.
Congress by action coupled with SCOTUS by inaction allowed a dual citizen at birth to usurp the office. It is an improvident act. The remedy is to declare it so, and find the actions valid by the peinciple of de facto officer.
What makes the US claim superior over Cuba’s? Subsequent residency and domicile, that’s all. At birth he cannot be viewed as belonging only to the US.