I'd like to think in part for us poor souls who must work on a Windows machine but are used to working in a Linux shell.
Every command is implemented in a module, it's just that pwsh ships with several core modules.
Instead, I get to use familiar coreutils primitives, while also benefit from the insane power of sane string handling, string interpolation, native JSON handling, records, scoping, etc. And forgetting so much bashisms that I groan when I pop a nix shell and end up in bash/zsh.
Honestly, nushell takes so little time to adopt and has so many tag-along benefits. The biggest friction has been around quirks of `mkdir`, `mv`, `cp`. Someone... I know... recently filed a bug on their `mv` not working right, so I am very happy to see this.