Yes! It's a proxy that might modify results on the way in or out, which proxies can do.
Could also be called a gateway, which feels a bit more accurate.
The same way API gateways perform additional services like rate-limiting and authentication and billing, an MCP gateway abstracts the services behind it and adds context such that an LLM can more easily interact with them.
More here (not my post, someone I know wrote this): https://hookdeck.com/blog/mcp-gateway
in this case, people are arguing it's a MITM attack, obscured by the MCP