A sweep may indicate a dominance (for one player over another) that makes the colors played irrelevant. Thus some people looking at the likelihood of black getting a win may want to ignore any sweeps. I gave both numbers so that the sweep could be included by those who wanted to and excluded by those who wanted to.
I don’t think the results of two games in one event demonstrates anything resembling “dominance” in chess played at this level. Do you think if this had been a quadruple RR Naka would still have swept him?
I had the same concern - too small a sample size. By this standard, the difference between a counted result and one thrown out for ‘dominance’ can be one bad blunder in an otherwise winning position.