Actually redneck is not derogatory from the workers point of view.
The term redneck was coined by the private police and armies hired by robber barons to kill unionists and unions in the mining industry.

Red banadanas and neck scarfs was the identifier among workers who chose to defy the bosses.

The other meaning of red neck from working outside in the sun is not all that derogatory in my book either.

Seeing that West Virginia was the setting of the wars against recnecks by goon squads, may be the reason that the meaning has become one denoting poverty. It was the fight against imposed poverty that the rednecks were dedicated.

The only people who would take pleasure in demeaning rednecks were the aristocracy.