A comparison of any British blues recordings with the original versions reveals that the late-sixties British blues groups .

remained less faithful to the old styles than their early-sixties predecessors had

Explanation:

grunge  bands  such as nirvana, pearl jam, soundgarden, and alice in chains broke into the mainstream, achieving commercial chart success and widespread exposure. punk revival  bands  like green day and the offspring also became popular and were grouped under the "alternative" umbrella.