You obviously don't cook or do science. Never cooked tortillas, potato chips, learned about properties of water or gases when heated. Or never done history.

Leavened or not, flat bread will rise like that, and historically flat breads wouldn't have been leavened.

Just sayin'

Yeast makes dough rise with lots of little bubbles while it's alive, not after it's been killed by heat. Baking soda and baking powder makes doughs rise similarly to how yeast does, but again, do pancakes separate like flat breads - pita, flour, and corn tortillas?