Yes. If we live in a simulation our subjective reality feels real, but it is in fact objectively a simulation. Someone may have created that simulation but that someone must live in either 'actual reality' or perhaps is also in a simulation. It cannot be godlike if it's also a simulation. Nor can it be considered so if it's subject to a reality outside of it's self which it doesn't have domain over.
Under that definition, Mormons should be considered atheists, as they believe that God was once subject to the same restraints as man.