From an enterprise adoption standpoint, remote MCP addresses the connector problem and can be easily retrofitted into enterprise-wide gateway services. In contrast, building tools is significantly more expensive for enterprises with large, existing API surfaces.
Most of the concerns can be addressed by a gateway service
But why the effort if a description (like OpenAPI spec) of your existing API is completely sufficient for using the API? A new and separate MCP service will introduce new and separate issues where the OpenAPI spec helps you strengthening your existing API.