Hi Luke

Thanks for posting in the community! Currently as you mentioned the only way for users to access your data in Lucidchart is by granting them edit permissions. However it is possible to link to external data sources (google sheets for instance) from objects within your document. Any user with view access would be able to follow these links. 

We are constantly looking for ways to improve Lucidchart! If adding the functionality you described would be useful for you please let us know via our feature request form!

As a note - it does say in the help when you click "learn more" in the sharing feature:

What if I share my data-linked document as “view only?” 
If you share a document as “view-only” then your collaborator will still see any data you’ve linked to your document including data that has not been attached to shapes on your canvas. Your collaborator can access this data by making a copy of your data-linked document. 

I was wondering the same question - it seems to imply that View Only collaborators would be able to view and access the data sets. I would like to be able for comment only collaborators to view the linked data for an object (without risk of them changing anything) - I can add to the feature request as well if this is not the case.

Hi Kendall

Thanks for posting! You are correct if you share a data-linked document with view-only/comment permissions the user will be able to access that data if they make a copy of the document (because they would own this copy and therefore have edit access). However they will not be able to see this data when opening the original shared document in comment/view only mode. 

If you would like for users to be able to view linked data without having to make a copy of the document please do let us know via the feature request form! Feel free to let me know if you have any further questions.