Installed Android 11 on my phone last night.
Went to share a recording of my commute to Google Drive this morning and it failed. Same with Dropbox.
Reading into it a bit it seems Android 11 has changed the way access shared storage. I used to store data (maps, recored tracks etc) on the SD card and the work around I've found (selecting "Shared Memory" as noted here
https://github.com/osmandapp/OsmAnd/issues/9857) doesn't appear to be an option when data is kept on the SD card.