Thank you for reaching out. Unfortunately not and this is by design, the intention is to keep everything within the same open workspace, each Collection being one, or part of a project.
respectfully, I don't understand how being able to save multiple projects would go against this design principle?
If someone wanted everything in the exact same project, they could do that, but having it so there is no functionality for multiple projects just means the program is limited for people who don't want that. I know for me that would just become overwhelming.
You already have saving and loading. I feel like when you drag a saved file over tape, it should just have a popup that asks if you want to add that file to your current project, or open it as a unique project (and it would just delete everything in your open window and then add the content from the file, as well as asking you if you want to save first)
I really don't see how this would make the product worse in any way, and I also really wouldn't imagine it would be hard to do.
Sorry if this came off as me complaining, or me being pretentious, I'm just sharing my thoughts on the matter and I mean nothing bad by it < 3