Why Are Quiet Spaces Disappearing? (honest-broker.com)

It predates Covid Bluetooth speakers on hiking trails were a thing even before the pandemic

Maybe it's the prevalence of noise-canceling headphones, especially the modern airpods-type bluetooth kind with active noise canceling. When "everybody" can turn off the noise on demand, noise is no problem. They also reduce the sensitivity of the user to their own noise, which might lead to making more. The modern culture of conspicuous consumption that demands loud and flashy probably has a part to play as well.

Not in Japan. So, perhaps a cultural thing?