FWIW this is also the main selling point of Zsh. I should go through this document in detail (thank you for linking it!) but a quick search shows that Zsh is not mentioned even once, and I think a Zsh comparison would be really valuable for people like me.
Or is it like Neovim vs. Emacs at that point, where neither one is "better" and it's just a matter of taste and/or whichever one you happened to try first?
The only thing to keep in mind about Zsh parameter expansion is that unquoted empty values will be dropped entirely, while quoted empty values will be treated like the empty string '':
cp itself should have been two commands, or at least accept two flags for those two very different semantics.
Actually there's a wave of unixy tools being written in Go and Rust and I think there might be a suitable cp replacement already, but it's up to distros to package it.
Or is it like Neovim vs. Emacs at that point, where neither one is "better" and it's just a matter of taste and/or whichever one you happened to try first?