Look, Mexico is 1/8 the size of the US and has close to 300 dialects, many of which has no written records.. It is, at this junction, impossible to determine how many more just vanished in 500 years after the conquest and to sift thru all that jigsaw puzzle.
The debate about who is a descendant from whom is not only insubstantial but also inconsequential. Part of my family descended from the horn of Africa, another from Spain, some from France and some even from China (got paperwork on it, by the way). That was just about 120 years ago. Now, can anybody take a shot?