unfortunately this PIC made the wrong decision
Avgas172 it must be wonderful to know exactly what went wrong thus allowing you to make your ill considered insensitive statement. Read the type of aircraft that didn't leave. Those pilots made the right decision in not flying that day but if they'd had 210s and the appropriate experience they may well have left with the other seven. I have operated in that area for 17 years in a C210 and know the forecast is often very different to actual weather and also can vary greatly over a short time period as well as a short distance.
By all accounts this pilot did not suffer from pressonitis and was very experienced in the area and aircraft type. It may well have been a case of the holes in the Swiss cheese lining up at the worst possible moment. Sounds like you've ruled out everything except weather, on very little information.