Yeah you can call the bread garnish until you get a dish where the bread is supposed to be the star. Bread is amazing. There are also sandwiches where the bread is a garnish.
I can tell you that a good tortilla is like 90% of what differentiates breakfast tacos from each other. The best of course have an amazing tortilla and great stuff to put in it, but the tortilla is the single most important thing. A bad tortilla isn’t something you can make up for.