I could see how many people would assume this, but it’s actually false.
There’s actually a big selection of dedicated audio players that do the job very well now. The battery life and audio quality are extremely good because there’s a niche market for them with a lot of competition.
If you think the iPod software experience in the early 2000s was good then you and I had very different experiences with iTunes during that time.
The resurgence of retro gear has a simpler explanation: Retro is cool. Vintage is cool. Has been for a long time. The reason we’re noticing it now is because the tech things we remember are finally passing that threshold where they go from being outdated to being retro. Just like clothes and styles that went out of fashion but are now retro-cool.