A few years ago we were able to upgrade everything (OS and Apps) using a single command. I remember this was something we boasted about when talking to Windows and Mac fans. It was such an amazing feature. Something that users of proprietary systems hadn’t even heard about. We had this on desktops before things like Apple’s App Store and Play Store were a thing.

If this actually were Linux's killer feature, then Linux would have had a much higher market share by now.

Make no mistake, this is my favourite feature of Linux as well, and I have never used a snap/flatpack/appimage in my entire life. But it doesn't have the kind of broader public appeal that you seem to be suggesting.

Yes. It's my way of voting with my wallet. I already have a few nice headphones and I'm not replacing them just because phone manufacturers are cheap and lazy.

Besides, I hate batteries. They always die at the most inconvenient time. And USB-c just for audio is way overkill.