How I think about this:

If you're using an agent in a shell environment with unfettered internet access and code execution: CLI + Skills.

If you're using a hosted agent on a website or in an app without code execution and limited/no internet access: MCP.

We want both patterns. Folks who are agro about MCP do ~all of their work in the former, so it seems pointless. Most people interact with agents in the later.