The comparison to app stores is interesting but I think MCP registries solve a different problem. App stores are for humans browsing. MCP registries are for agents discovering tools at runtime based on the task at hand. The user never browses — they describe what they need and the agent finds the tool.

That is a meaningful distribution shift. Products no longer need to be marketed to end users if an agent can find and invoke them directly. Skills require the developer to install them ahead of time, which means someone already decided this tool was relevant.