What makes St. Anger by Metallica notable?

'St. Anger' debuted at number one on the Billboard 200 chart, reflecting Metallica's enduring commercial appeal despite mixed critical reviews. The album's unfiltered approach and personal themes resonated with fans, helping to spark discussions about mental health and addiction in rock music. Released in 2003, 'St. Anger' marked Metallica's first studio album since the controversial departure of bassist Jason Newsted in 2001. This album represented a significant shift as they embraced a more stripped-down sound, moving away from the polished production of their previous works.