Not that I agree that NixOS installation should be graphical or any easier (it should be easier but won’t help in long term adoption) perhaps somebody could point out what ehxactly are the pain points? In the “worst” case, there could be a TUI?
I see only two things- one is (even scary to me who claims to have written an x86 bootloader) disk partitioning. Other, before that is starting internet. Are there even any other steps in existence? For the latter we could just have iwd as default. Which has a much simpler interface using iwctl tui. No more wpa_supplicant and it’s quirks. But even otherwise, there could be a tui that asks user to enter username and pwd for wifi, and do a rebuild switch in the live environment (if it works at all).
Also, disk partition has a TUI tool available too. And the graphical Live CD o lf course comes with gparted.