I interpreted it to mean, that when a bag is a trendy, it gets mentally tied to a very specific decade and aesthetic.
Fendi Baguettes feel like 1997-1999 to me; they look like tight jeans and peasant blouses and sipping wine out of plastic glasses in the park; Dior Gauchos feel like 2000-2005; 5" heels and pencil skirts, studying poetry and attending gallery openings (mostly for the food).
I'm currently trying to cull my bag collection because there are a lot of bags I don't carry. But there are some I haven't been able let go because I had such visceral reaction; like a fashion scrapbook of I person I barely remember.