Whatever world the author looking to return to, presumed lost due to technology, where people were present and engaged in a crowded social situation, never existed.
I've spent a cumulative total of four years in Japan, most in the 90s. Here is a video that demonstrates the typical pre-smartphone Tokyo metro riding experience, which replicates my memories precisely: https://youtu.be/hyK3-w1TIyg?si=uXzm0G5pUvrvkw78&t=270
Based on the other blog posts it appears the author is too young to remember a time before smartphones.
I want to assure them that smartphones are much better than the alternative, one of which was (having forgotten my book) sitting staring at the seconds hand on my dive watch, spinning the bezel over and over again until realizing that the barely-audible clicking may be disturbing another passengers, and then stopping and just staring at my shoes for 30 or so more minutes.