I think the least that distros can do, is allow listing all packages and system settings in config files like .toml rather than having to type in every single package to install, or click through system setting GUIs to setup. Would that require using a whole programming language or system like NIx?
While NixOS works much differently from most distros, that's the only reason I use it: package and system settings in text files. If I fix something, it's fixed permanently, I don't need to hunt down files in random directories if I want to change a setting. If I ever need to reinstall the OS I don't have to write dnf install every single damn package and manually setup all that up all over again. Having daily-drove Windows macOS & Fedora as throughout the years, my setups have felt hacky as well as houses of cards as I've wanted or had to set them up again (I don't mean Fedora specifically, but distros in general).
Basically it feels insane that it's the way most linux users and servers in the world operate. If I, a humble computer hobbyist can figure out Nix, why don't more users do so, and why is Nix so niche?
Debian's installer accepts a preseed file that will automate answering the questions it normally asks.
You can also ask Debian's package manager for a list of packages marked as manually installed (
apt-mark showmanual) and then use it to install those same packages on a fresh system. I think there's a more formal way to do this as well, but I haven't needed it in so long that I forgot the details. :PAs for why most distros don't consolidate all the configs for all system components in a master text file, I expect the main reason is the Unix heritage: A great many of those components have been around for longer than Linux has existed, or derive from those that have, and their configurations evolved separately. (Almost all of them are configured with text files, though.)