I predict there will be some sort of package manager opensource project soon. Download skills from some 3rd-party website and run inside Claude. Risks of supply chain issue will be obvious but nobody will care - at least not in the short term.
They've already started a public repository here: https://github.com/anthropics/skills (It's the last link in the "Getting started" section of the post.)
They already have the Plugin Marketplace [1]. It's all too much of a fast moving target for something as rigid as a package manager I think. Open source projects for now will be limited to Awesome-* collections [2]