Actually most miners have tried to get the best possible hash per kilowatt ratio out of their cards, which makes sense given that electricity cost is basically

Actually most miners have tried to get the best possible hash per kilowatt ratio out of their cards, which makes sense given that electricity cost is basically the main cost of their business. And the best ratio isn't achieved by overclocking and -volting, but by undervolting and underclocking. Very constant workload, way below peak capacity - I bet that crypto usage does put much less wear and tear on the chips than heavy gaming use.