Thanks for posting in the community! Unfortunately, viewing a list of comments for all folders/documents at once is not currently supported in Lucidchart. However, we're always looking for ways to improve Lucidchart, and your feedback is the best way for us to do that. Would you mind adding your idea to our feature request form? Ideas submitted to this form are passed on to the product development team for their consideration.
As a growing company, we take our feature requests very seriously. We are continuously looking for how we can make our product more useful and effective for our users and we pass that information directly to our product development team. We apologize if this hinders your work; please let us know if we can support in other ways.