It's not shiny but it does work. Continuing to use abusive software is a disservice to yourself and everyone around you.
If current GNU/Linux phones work for your needs, that’s great - but sorry to say that you are not representative of all users (neither am I - that's the point, kind of - Android/iOS are mature enough to cover most users' needs). I don’t want to go into too much detail of my specific needs, but let’s just say the deficiencies boil down to (a) vastly inferior power management/battery life, (b) vastly inferior processing power in the current crop of hardware and (c) specific apps/services not being available on the platform (and likely impossible to run via Anbox because of (b)).
I would actually love to jump to a GNU/Linux phone. Less so because of freedom or privacy concerns (they are a factor, but not the dominating factor). More because I prefer the traditional desktop/general-purpose-computing OS way of doing things (file-centric vs app-centric, root access to the entire file system, development directly on the device). I would honestly be fairly happy with Android if it was pre-rooted, imposed fewer restrictions on what apps can do, and was based on a mainline kernel ideally.
I have previously used Ubuntu Touch for about a year on a secondary device, I have a Librem 5 on pre-order, and I follow development for the Pinephone somewhat closely and am tempted to get one. But for the foreseeable future I can't see a GNU/Linux smartphone replacing my Android - I'd see it as a complement to it (a tiny portable laptop).
* Google services for work / school
* Facebook / Whatsapp / Instagram for keeping in touch with friends.
* Spotify, Netflix etc.. in good resolution
* Many other specific apps.
It's not all black and white either. Traditional linux doesn't sandbox software. Android does sandboxing pretty well.
Building an alternative phone OS is much harder than building an alternative desktop OS—the requirements are much higher (battery life, cellular, app support) and the mobile web is far less developed as a stopgap compared to the desktop web.
Desktop Linux is usable for most developers and people who don't care about UI consistency or proprietary applications like Office and Creative Cloud. That's a reasonably significant chunk of the computer-using population. The same cannot be said of phones.
I haven't had it working on Android or iOS for years, only realising when it accidentally tries to send.
I just assumed it didn't work because nobody cared.
I think it would be good to point out that MMS often doesn't even work on android phones. So making that a requirement is a bit silly.