My guesses are: A universe that did that would have too much energy (from the mutual annihilation) once the orders and orders of magnitude of "extra" matter/an

My guesses are: A universe that did that would have too much energy (from the mutual annihilation) once the orders and orders of magnitude of "extra" matter/antimatter interacted to make that likely/possible. Wouldn't we also see clouds of antimatter just hanging around? What proportion of matter has ever interacted with anything else? My guess is "low".