Android storage twice offline

[Andrew H.44]

Out of my more than a TB of Dropbox files, I have made a few thousand, amounting to a bit less than 9GB, available offline on my Samsung android tablet (Android 10, One UI 2.5). These are mainly papers and small data files I use professionally, and selecting them has been quite a bit of work.
Although I have only 9GB of offline files, Settings 》 storage and several file and storage manager apps report that Dropbox is taking up almost 21 GB, even _AFTER_ I have cleared the cache. I have several questions.
1. Is this normal? Should I just expect Dropbox to occupy twice its offline file storage?
2. Assuming "no" to (1), if I reinstall the app, which seems to be the most common advice from Dropbox's own help staff, will Dropbox remember which files I made available offline, or will I loose all the work that went into selecting offline files?
3. Assuming reinstalation forgets my offline file selection, and excluding clearing the cache, which I have already done, is there any way to reduce the excess storage space above that occupied by offline files that Dropbox occupies?

[Lusil]

Hey @Andrew H.44, thanks for posting here. 

Generally, if you reinstall the mobile app, any offlined/cached files being removed from the device. 

However, just to make sure that we're on the same page, could you clarify where you're seeing that the mobile app is taking up so much space, even after clearing the cache?

If you could send us a screenshot, that would also be super helpful. 

Looking forward to hearing back from you!