My older pitch from 2020 (thanks for linking!), covered unapplied methods, but went a bit more in depth covering motivating use cases, design details, and corner cases. You might want to study (and steal freely from) that pitch and the attached discussion:
In particular, it addressed some questions about labels, generics, and mutating methods that have come up in this discussion.
You’re welcome to steal text from that older pitch as far as I'm concerned.