I would assert that what most people think of Mexican cuisine is actually Tex-Mex cuisine....big difference.
I agree it’s a big difference.
But you probably not find as many Mexican restaurants as in LA. We have Mexican restaurants that do Oaxaca style, Poblano style, coastal style with fish tacos, Mexico City style, Barbacoa style and just the generic Mexican with tacos, tamales, soups, meats, etcetera. Those are NOT Tex-Mex. And they are wildly popular.
Texas may have them, I don’t know to what extent they depart from Tex Mex ... we do. And masa is Mexican by nature for tacos, tamales hopes, et al.