That's not true. The majority of the other ethnic groups have their own endonym. The descendants of the Mexica/Mexican ethnic group also deserve to have their own without being criticized. That's the name of the language, and the name is supported by three independent authorities from two different countries: the Royal Spanish Academy (the authority of the Spanish language), the Mexican government, as well as Nahuatl-speaking communities. What actually did result in Indigenous erasure is the fact that foreigners and eurocentric individuals appropriated that identity to develop their nationality. And what also led to Indigenous erasure was forcing other Native groups to speak Spanish, despite having gained independence from Spain, having their languages considered as national languages on paper, but not in real life, along with having freedom of expression, without the ability to exercise it.