Shock value was always in pop culture long before Gaga was born.
That's because it's talking about the CURRENT era of pop music. Not many other mainstream artists have done it like Gaga since maybe the 90's-early 2000's
Well she did start the trend for over-the-top spectacles during performances. Before her, it was all about dressing a certain way and gaining as much "Regular" appeal as normal.
Katy Perry’s palling around with Left Shark and Miley Cyrus’s every aesthetic choice both owe something to Lady Gaga, who was the first dazzling weirdo to provide enough material for the web’s endless churn