I don't see a reason to support MCPs by default. Pi is so extensive and has such a rich plugin ecosystem that MCP support is just one "pi install npm:pi-mcp-adapter" away.
Or you may choose another plugin that works differently.
That's the whole point of extensible systems like Pi or Emacs, you don't need to pray that maintainers will have the same vision as you, you just pick one of the many alternatives instead. Or ask pi to write one for you.