Metro population is a regional statistic that includes surrounding areas. Charlottes and Seattles value likely improves as you look further out. Not sure about Sacramento.
But it's not just population but regional corporate wealth as well. In that aspect the SF / Oakland area 90 minutes away and the Seattle areas likely have huge advantages.
I do statistics for a living. One thing of note in those statistics that is left out is population trends and projections. Charlotte has one of the fastest growing metro areas in the US. In the next 10 years or so it will be near or in the top 20 if you look at the trends.