Doug's post is about the upcoming Swift 6 language mode. Adding a centralized package registry doesn't require a language mode, so you shouldn't expect any discussion of that here, no matter how interesting or important it might be.
You might have missed it, but we did make a blog post about a month ago talking about more general project priorities and upcoming work, and it does include information about SwiftPM and its work towards a package registry. If you'd like to talk about that, you might participate in the forums thread about that post, or you could find / start a thread in Development > Package Manager.