However it appears to underestimate traffic delays for DC->OBX beach traffic. On a summer Saturday morning, that’s a 6-7 hour drive. Or worse. Apple Maps has it closer to 5-5:30 for most of the day. Google gives a range from 4:45-6:30 - 4:45 is basically impossible any time of day and year but 6:30 is ballpark-ish if you don’t hit a major traffic jam.
But maybe that’s a worst-case route.