Notice that the article omitted a critical bit of information?
Though Mr. José Zuniga is registered to vote, is he a citizen? All they say about him is that he was a “former migrant worker”.
Importantly, the US border with Mexico has long been so porous that lots of Mexicans lived in Texas, some even commuting back and forth. Every morning for many years there would be a stream of many Mexican children crossing the border to be educated in Texas schools, then returning to their parents homes in Mexico at the end of the school day.
So unless Mr. José Zuniga can establish his identity as a US citizen through the use of other paperwork, enough to get a photo ID, he is likely to be and remain a citizen of Mexico, whether he is registered to vote in Texas or not.
This is STILL happening, at least here in New Mexico- did Texas stop it? In my area the only change is that now the school bus from the U.S. is not allowed to cross the border into the little town ACROSS the boundary IN MEXICO to pick up students at their door to bus them back to U.S. for school. Yes, until recently the school buses went across and picked up students in Mexico...amazing, but true.
Citizens that did not agree with students from Mexico going to school here tried to stop it, but were told most of the students crossing from Mexico are U.S. citizens so they should be allowed to attend school here. They are U.S. citizens only because their mother crossed the border to have them in a U.S. hospital for citizenship- though they have no ties to U.S. the babies can get on the gravy train starting with being educated here.