I have not seen in any feature roadmap. It does sound like an easy feature to move files much like a 1:1 space and then moving it to a space with more than 2 people and moving the content which forces me to create a new room and upload everything again. The original feedback was it would defeat security and allow folks to move files from a 1:1 which they should not but then I knows slack posts a message asking if files should be moved or not so same process can be followed here.
To your request only issue is one again security/privacy but balanced with flexibility. I would post this from spark as a feedback if u haven't done it already
