Well I suppose Miami-Dade is hard to see, but the RGV really highlighted the Democrats *even worse* performance among rural-working class voters of all races. The RGV is just the next tale in the story of the modern Democratic struggle to receive the working-class vote. Democrats mustn't lose any further ground in working-class America, or Pennsylvania might be gone.
Pennsylvania is hardly the bastion of working class America. It's economy is quite white collar. Philadelphia and its Dem-friendly suburbs are growing (albeit slowly), as well as the Allentown area too. The Pittsburgh area is no longer seeing steep losses either. Maybe Michigan fits the profile of a working class state better.
Yes, that was a bad example. The areas you mentioned are white-collar but I suppose a better term is rural instead of blue-collar. The same trend is similar, in my opinion, to the RGV. Dems believed the slip of rural voters was limited to white voters, however, this election shows that to be untrue. Dems slipped this election in rural areas regardless of color whether it be the Mississippi Delta, the RGV, or Southern Ohio.