Presumably though the domestication of wheat had a symbiotic relationship with bread making. The (ancestral) wheat that exists today is like bread-powder when it is milled, but it was probably bred for that purpose (no pun intended). So I’m not sure we can be confident what the first breads were like, made with whatever pre-wheat grasses they had at the time. Perhaps it required other ingredients at first before those aspects were “automated” into the grass itself, etc