Are they using any original GNU coreutils code as reference? My understanding is nothing is 1:1. They're trying to build, from the ground up, a totally new codebase that has the same user-facing functionality but under the hood is idomatic Rust code (so nothing like the GNU C code)
They are recreating something that matches behavior not using licensed GPL code. Which is the same way the GNU coreutils were a recreation of the proprietary Unix tools in an effort to provide open source alternatives.
Like you wouldn't say "An appropriate amount of work to slap a GPL license on somebody else's work" in reference to GNU recreating the Unix tools, so why say it here?
