My company uses MCP in production to connect different AI products together that were developed by different teams. It makes the connections very easy, where a REST interface often has quirks and features that you have to understand.

That's fair. REST isn't much of a standard. MCP can be just as badly designed and documented as REST, but at least there's a standard for authenticating and listing the options. Reading through other top-level comments, this seems to be the theme. MCP usage is mostly driven by ease of connection.