Why would I do this over a Synology DiskStation which allows me a hassle-free way to stream my music anywhere I have a internet connection... I use it daily in my car without a problem, going on my 3rd DSM and ~10 years of this setup.
For me, the reason is that Synology is not open source, and additionally because their NASes are overpriced for their size and capabilities. I have a 12 disk NAS that cost me a total of $500 (before drives), with no software licensing fees at all, and that's not even an especially cheap one. My earlier NAS was slower but only $120. Of course, it needs a deep 19" rack to mount, but that's actually an advantage for me, as I have a dedicated homelab rack to play with.
Dedicated NAS hardware is often pretty efficient. The Synology DS224+ (a 2-bay model) for example claims to idle at 4.41W when the drives are allowed to hibernate. That's within spitting distance of a Raspberry Pi, and a lot better than most people will be able to achieve with repurposed desktop/server hardware. Lots of desktops will idle at tens of watts.
If you keep your spinning rust drives spun up all the time, it's another 5ish watts per drive.
Peertube has existed as web-based software for years; this post is about the addition of a mobile app. The linked project page has a search from the big "browse content" link at the top and a list of servers running Peertube, such as https://fedi.video.
For onboarding a general audience, this project page is not ideal.