The one that led to McBling and Reality TV. I wouldn't try to force fashion to remain shiny bubblegum pop grafittipunk/shibiyapunk futurism to stick around or anything, I just think it had more staying power under normal conditions that was lost solely due to the nature of life from 2001-2008.

People don't change fashion at the drop of a hat for financial crises, that just strengthens counterculture and futurism. They change their tastes suddenly when innocent people die in a new and unexpected way. That's why art from the time period just before and during the Black Death is filled with more cynicism than even the past 7 years (roughly since Trump was elected), why an Oriental symbol of peace was ruined by the Nazis, and why the climate crisis has made FairPhone the only smartphone brand that survives without shoving ads down your throat.

Or at least, so it seems to me, I'm not a sociologist. What I also am not is petty or authoritarian, I'm not trying to make everyone wear 30 year old clothes or check their emails on an iLamp computer. I just know I'd like to see a world where people don't have to rely on mass production to provide the things we need to live, because then you're required to change your stuff out the moment it's broken or obsolete.

My point is, I was trying to say your idea would make planned obsolescence and obsolescence in general themselves a relic of early civilization, so limiting such a world to one genre or style of product that only remains popular for ~10 years before becoming nothing but zeitgeist and nostalgia feels needlessly restrictive. I can see how it could be taken the opposite way, sorry about that!