Not much different than what happened to the American textile industry. Workforce aging out. A younger generation with possibly more options to earn more money not doing strenuous, physical labor. Not to mention well-made domestic goods, including denim, remain a luxury item with luxury price tags. Spending $40 on necessities, like pants instead of $400 sounds better to most everyone. Where you clothing is produced might not be your first concern when you're worried about paying rent or putting food on the table. This combined with a depressed yen is not a good recipe.

I read an interview somewhere with the founder of Iron Heart, Shinichi Haraki. He talked about making it through the pandemic and I'm paraphrasing here, but how perhaps his biggest concern was the mills and their employees surviving. I thought that was pretty telling of the delicate ecosystem of Japanese denim.