Based on the knowledge sources provided, there are issues reported regarding connecting to standalone MongoDB instances using Airbyte. However, it's not explicitly stated in the sources whether there are plans to introduce support for this specific functionality in the future. In one of the [Github issues](
https://github.com/airbytehq/airbyte/issues/35621), a collaborator mentioned that the issue has been marked as stale due to inactivity and it's not clear if it's still reproducible on recent versions of Airbyte. They also encouraged community involvement to improve it. In another [Github issue](
https://github.com/airbytehq/airbyte/issues/28024), it's mentioned that Airbyte has introduced robust updates to the MongoDB source connector, but it doesn't specifically mention support for standalone MongoDB instances. Therefore, while it's clear that Airbyte is actively working on improving its MongoDB connectors, it's not explicitly stated whether support for standalone MongoDB instances is part of their future plans. I would recommend reaching out to the Airbyte team directly or participating in their community discussions for the most accurate and up-to-date information.