Linux

We're appreciative of your considerations and reservations. However, some of your views seem unnuanced at best or plain biased at worst.

The problem is all the apps and things you may wish to do with your OS.

I'm aware that the rest of the comment goes over this. But, I hope the mention of "all" here is merely an oversight.

Flatpak is the preferred method of installing apps as it doesn't interfere with the OS, but that is a compromise that means more overhead for running apps including memory and disk space

While that's technically true, a (relatively) modern device wouldn't even care. I don't recall OP mention their hardware specifications; but if they're perfectly capable of running VMs, then I don't see why they would be bothered by this (almost) unnoticeable amount of overhead.

its a work in progress

Sure..., but we're not talking about alpha, beta or even RC software. Like, I'm not sure if you're aware, but you make it sound as if it's very new and/or immature. Fedora Atomic has been in the works for over 10 years. It first released their Fedora Atomic Host (currently known as Fedora CoreOS) in 2014 and later released Fedora Atomic Workstation (currently known as Fedora Silverblue) in 2018. Heck, Fedora has already put so much trust in their Atomic branch that they intend for 2028 that immutable variants are the majority of Fedora Linux in use.

By contrast, what is it that you base this statement of? That it receives very active development that most other distros would be jealous of? That it rapidly implements all kinds of new features that you're having difficulty keeping track of?

and with significant compromises at the moment.

This is a big claim. But I haven't seen enough in your comment to substantiate this. Your two best claims are:

• Flatpak is the preferred method of installing apps as it doesn't interfere with the OS, but that is a compromise that means more overhead for running apps including memory and disk space, and less integration with the host OS than traditional apps.

Which is a problem of Flatpak on all platforms. The very same Flatpak that was recommended by people associated with Steam/Valve for Ubuntu. Furthermore, if OP creates their own image, then this isn't even an issue; they can practically bake whatever they want into their image. There are also multiple tools to get this going. I achieved it in a weekend (as a noob) last year, so it ain't hard. Finally, 'over-reliance' on Flatpak is not even a thing on Guix System and NixOS.

• You can overlay native apps but the more you overlay onto the immutable os, the more complex upgrading gets and the risks of breaking stuff.

This is not an issue with your own image. If the image itself is busted, then it doesn't come out of the pipeline. Hence, the busted image would not have been delivered to your device in the first place. And, again, layering isn't a thing on Guix System and NixOS. Hence, this problem doesn't exist for them.

Your VPN may just be the first of many programmes you find you need to overlay.

Do you (for some reason) imply that layering is necessarily a bad thing?

If your needs a re very simple then maybe it'll be easy, but if you're using lots of software and tools (particularly if its not available Flatpak) or custom OS config you may find atomic desktops are not yet quite ready for you.

I have yet to receive substantive evidence from you to support this view of yours. I hope you'll deliver...

It could be frustrating and off putting if you try linux immutable, find loads of problems and attribute that to linux when its actually the immutable OS that's the cause.

I could change the word "immutable" in the above sentence to "traditional" and it would have been an equally nonsensical statement.