Let me begin by saying that Marques Brownlee is one of the most beautiful men on this planet, but I would watch his tech-review videos even if he weren't. Not all of them, because some are about high-end toys that are of little or no interest to me. But this is one of his best: not just for the "Gen X Mets Old Tech" angle but for the interviews with older people (Millennials?) who remember the introduction and marketing of the Walkman, an even older person (Boomer?) who worked on the original development team -- and then a comic bit about trying to repair a broken one.
A couple of things I want to quibble with, however, partly because I've heard one of them before. One is the idea that the idea of "portable music" that shut out the rest of the world was completely new. When I was a sprout, there was something called a "transistor radio."
True, there are differences. With a radio you have little control over the music you hear, except by changing stations. There was no stereo radio in 1961, so you only needed, and only got, one earbud, and the world was not completely shut out. As I recall, though, there were adults who claimed it would allow teenagers to isolate themselves, cause juvenile delinquency, and bring about the end of Western civilization.
Brownlee's video wants to give the impression that boomboxes, the previous stage of portable music, were "social," in that you "shared" your music with those people lucky enough to be around you. Perhaps; but they were also notoriously antisocial.
I haven't encountered many boomboxes on public transportation in the past decade, but I have found people (usually old enough to remember boomboxes and the Walkman) who play their smartphone music loudly enough to annoy, loudly enough to be heard at the front of the bus from their seats in the back. Oddly, it's been rare that I've noticed kids do it. That may not be courtesy, it may just be a lack of interest in sharing one's music with strangers; it's a very private thing, after all.