Those aren't competitors of Spotify/Netflix; they're alternatives for people who are willing to tolerate small inconveniences to have full control over their library.

Of course it's not as easy as signing up for Spotify/Netflix, but setting them up is easier than ever (even easier for tech people).

Yup, the key word for me is control. And over time, considering the continual loss of control, more people will adopt self hosting, and things will get better and easier. For now, i only recommend it to hobbyists or people with free time and money. It does take quite a while to get it all running smoothly.

Cheaper too.