There's an FHS emulating option for guix shell containers that has been proposed (it needs some minor code changes but is functional; I use it): https://issues.guix.gnu.org/56677
So doing a guix shell --container --emulate-fhs <packages> will have you in a container with the usual /lib, /bin, and so on, which should work just as a "typical" Linux distro. You'll want to share things from the host to the container (e.g. graphics) but that is all standard guix container options.
That is very cool. Could one then persist binaries built against such a container with something like `guix pack`? That would be absolutely killer. (Not reproducible at all, but an awesome escape hatch for building software in a traditional way, ad-hoc and imperative, on GuixSD. Could be really nice when packaging an odd piece of software feels overwhelming.)
Either way, that's pretty exciting and I hope it can be merged soon!
I'm not sure how that could work exactly, but yeah, did think of some sort of guix shell build environment container. Though I guess inside it should be the same as "regular" Linux, but you've specified the environment exactly (i.e. you could capture the exact Guix commits to make a reproducible container). Unfortunately, once in there you have state to worry about, so you'll lose reproducibility control as you say, but do think there could be some way to make this a nice stop-gap.
So doing a guix shell --container --emulate-fhs <packages> will have you in a container with the usual /lib, /bin, and so on, which should work just as a "typical" Linux distro. You'll want to share things from the host to the container (e.g. graphics) but that is all standard guix container options.