No, it’s a taco, because the bun is one piece rather than two, as required for a sandwich.
None of these definitions are universally accepted.
A taco is a sandwich A hot dog is a sandwich A burger is a sandwich
There is such a thing as an open-faced sandwich, which has one slice of bread.
Therefore subs are tacos? Or the two-piece requirement is too strict https://www.kingarthurbaking.com/recipes/italian-sub-rolls-r...
None of these definitions are universally accepted.
A taco is a sandwich A hot dog is a sandwich A burger is a sandwich
There is such a thing as an open-faced sandwich, which has one slice of bread.