The old unions had good and bad, they enforced total inflexibility and demarcation amongst the the trades which helped no body... They also fought tooth and nail for rights and pay..
Your beloved Thatcher and prior chose not to modernise/ invest in heavy engineering, they put all there eggs in one basket, so instead of being world leaders and specialising like the germans and norweigens, we did fuck all but close factories and shipyards and replace them with minimum wage call centres decades later... amazing skillsets lost...