I agree to a point. Singer Brian Johnson's voice is fingernails on a slateboard in the way that GNR's Axl Rose's voice is. But AC/DC sounded great on their 1978 album Powerage, when they were fronted by Bon Scott. Unfortunately, Scott died of alcohol poisoning in 1980, and they made the mistake of thinking they could replace him with Johnson. Wrong.
I so disagree. Bon Scott was a terrible singer. There music did not get good until Back and Black came out.....that album pretty much defines Rock n Roll as we know it today.