Both Bianca and Mick Jagger wore YSL at their wedding.
Saint Laurent also set the standard for celebrity excess. His pre-collection mini-breakdowns were famous (and in fact parodied in one of Harold Robbins' trashier trash novels, "The Adventurers." ) He posed nude for a fashion magazine well before every Tom, Dick and Myle Cyrus was doing it. He used drugs, he drank to excess, he became a recluse, but he always managed to produce fabulous and newsworthy fashion.
In the 60s and 70s the only magazines my parents subscribed to were "Life" and "Newsweek." I can still remember the fuss those rather staid magazines made over YSL's Mondrian dresses; you'd think he invented a vacine or something. His release of Opium perfume created another media sensation. Imagine, someone glamorizing drugs -- in the 70s!!!
Saint Laurent abruptly fell from fashion favor in the 1990s. He didn’t do minimalist and he didn't do grunge, and after 30 years on top of the fashion heap, he probably didn't care, either. Then, after he retired in 2002, he simply disappeared. Reading articles about his death online I came across many a reader comment that said “I thought he was already dead.” Look upon his works ye Mighty, and despair.