Not only is UPnP a security risk, it'll work only if a user has an IP that can expose ports. IPv4 addresses are becoming rarer on home networks and CGNAT connections can't expose ports even if one turns on UPnP.

Sure, yeah, taking on the Pixel without specifying the number of years of OS and feature updates and without GrapheneOS support. Pretty good title for the post

There isn’t one. Maybe Fairphone 5 but even with custom ROMs, running Play Services as a sandboxed user app isn’t possible. And even vanilla iPhones can’t be as privacy oriented as GrapheneOS is.

You cannot listen from multiple devices at the same time. You can have multiple logged in, but only one can be actively playing a time.

This wasn't my experience. I was logged into Apple Music on my iPhone and whenever I logged into Apple Music on my web browser, it did play music for a while but then music would stop playing randomly and I was told something similar to what you mentioned about only one device being active. I had to reload the page to make that warning go away but it came again after a while. This was when Apple Music wasn't being used on my iPhone, it was just logged in.

I don't see how Apple Music can be considered a useful streaming service with this limitation unless one doesn't possess more than one computing device (literally just an iPhone, or just an iPad, or a just a desktop/laptop and nothing else). Sounds absurd. This isn't an issue with either Spotify or YT Music.

Can I listen to Apple Music on my desktop on a web browser while being logged in to Apple Music on my iPhone/Android? The last time I subscribed to Apple Music (back in March or April 2023), it didn't allow being logged in and playing music on multiple devices simultaneously.

It is. Those fake accounts that Aurora Store uses stop working randomly. I learned the hard way to never rely on Aurora Store ever again and just use sandboxed Play Store on GrapheneOS.

There seems to be a known bug which prevents people from subscribing to communities on different instances.