Comment by kkfx

You have a statistical point of view that doesn't go into detail enough: yes, Debian, Ubuntu, Mint are mainstream distros and use ext by default. The vast majority of their users are also mainstream users and would never approach declarative distros, which are alien to them.

Those who choose going declarative instead are people with operations knowledge, who understand the value of a system ready to be built, modified, and rebuilt with minimal effort thanks to the IaC built into the OS, who understand the value of their data and therefore babysit them properly. The average user of Debian, Ubuntu, Mint today doesn't even have a backup, uses someone else's cloud. If they run experiments, they waste storage with Docker, or use manually managed VPSs; they don't own a complete infrastructure, let alone a modern one.

So thinking about them for Guix means never letting it take off, because those users will never be Guix users. ZFS is the opposite of complicated; it's what you need to live comfortably when you know how to use it, which unfortunately isn't mainstream, and declarative distros do the same.

NixOS succeeds despite the indigestible Nix language because it offers what's needed to be comfortable to those who know. Guix remains niche not because of GNU philosophy but because it doesn't do the same, not offering what those coming from operations are looking for and they are the most potential realist target users.