Are subfolders an option in Goodnotes 6?

The ‘try this idea’ would work better if we had the ability to link to a notebook or folder within the notebook itself

Just use multiple notebooks and subfolders instead.
A structured and collapsible outline would be nice though ( just like imported pdfs have)

What a fuss...you tell me creators of this app....how you’ll organise if you have 50...100...500 files and all are stacking up and up...

Yes, this. My project notebooks often contain sub-projects, results of sub-projects, and sometimes sub-sub-projects, etc... The ability to group information into folders or ‘sub-notebooks’ would be a huge improvement.

I’m currently attempting to manage my ever-growing collection of data using bookmarks like these:
Project_1
Project_1_Results
Project_1_Modifications
Project_1_Meeting_Notes
Project_1_1
.
.
.
You get the picture.

Folders (or nested bookmarks), please!

I can't use it because i have too many classes and it's too unorganized

Absolutely. My app is starting to look like an unkempt, disorderly desktop. When and if folder implementation becomes possible, it would be nice to be able to zip the folder and download it on my PC as the .pdf with "writing / editing" saved from my reading and remarks. This would enable me to write on my own books without the need for taking up physical space in my library. This would be SO awesome. Thank you in advance for considering this.

I use the bookmark functionality to do that. Works really well.

Yeah I would love this!!! make it work in terms of how folders work within Apple Notes.

Since in Apple Notes You can have a Main Folder > Sub Folder > sub sub within the first sub folder > so on

Love this! But it needs to be thoughtfully done. So your bookmarks are a nice start to this. Marking your thumbnails could be a part of this, but just useful bookmark management could work well.

One note and Outline+ have the concept of a notebook. In them, sections of the notebook are in tabs across the top and pages (that can be more then one page long) are in tabs along the left side. Both the sections and pages can be renamed. This scheme works well for hierarchical structuring of notes and greatly facilitates navigation.
ScribeWithAStylus

It would be nice having tabs inside the notebooks rather than folders!

Totally AGREE!

Isn't this like tabs at the side or something? I guess you could also list pages by their title or first line, similar to the bookmark list.

I'd like to see a similar design to pages and keynotes when browsing folders

This would be great. But why not just also generalize categories to allow more levels than 2.

This would be helpful - but please consider adding a view that allows the user to see more notebooks per page so we can scan quickly to find the one we want. Seeing the entire cover in the category is not as helpful.

Maybe have "binders" within categories. Within a binder you can have multiple notebooks and/or loose pages. Example: I have imported study guides for multiple exams into my "physics" category, but they are all separate and creating clutter. If I were to put them all into a notebook, they would blend together and it would be difficult to quickly find a particular study guide. If I could drop them all into a folder, or a "binder," I could then open that binder and see the individual study guides grouped together.

I came here searching for this. I love GoodNotes, but this really needs to happen. I'm having an awful time keeping stuff organized in the app because this is missing.

I'd be happy with just being able to name my notes within a notebook.