I actually don’t think that the “It bag” has disappeared. I would argue that the Balenciaga cagole, YSL quilted tote, and dare I say it… the MJ Tote bag are huge. Also, a lot former it bags like the Baguette and Saddle are very covetable now.
I think one reason why they’re no long a phenomenon is due to fashion not being aspirational anymore. Luxury has almost become the standard. For example, more and more consumers prefer buying a pair of Balenciaga sneakers over a pair of Nikes. It bags were status symbols. But now that “fashion is for everyone,” I don’t think they carry as much weight. Unless you’re carrying an Hermes bag, no one cares.
Also, I believe the way we consume media has impacted “it bag” culture. Tabloid magazines and entertainment news programs were huge catalysts to a bag’s success. Instead of a bag having organic growth through paparazzi images, brands now rely heavily on paid partnerships from a handful of influencers. Brands market bags now like pushy salespeople at a boutique. Its very inauthentic.