My experience with the new Rich Text editor mode has been very frustrating. I love the way we can place a document in an assignment with that new Insert tab. However, it turns out that the files you place are NOW placed in a folder called "Uploaded Media" instead of just in Files. Since I didn't know that was what was happening I ended up re-uploading the document to Files, then re-editing the assignments.
My beef is this: what files in my Files folder weren't "Uploaded"? I'll answer that: none of them. They are all uploaded! Why a new folder?
Although I don't mind the new folder, my concern is wanting to organize my uploads into subfolders. I see there is already an idea to promote: https://community.canvaslms.com/t5/Idea-Conversations/New-RCE-upload-into-a-subfolder/idi-p/369911