Support to shrink a F2FS partition ?

[jebez1]

https://en.wikipedia.org/wiki/F2FS#cite_note-15
https://www.mail-archive.com/[email protected]/msg04247.html : " Currently, it doesn't support shrink an image. " , why ?

Otherwise there's the method :

Back up the data on the F2FS partition .
Delete the partition and recreate it with a smaller size .
Format the new partition with F2FS .
Restore your data from the backup .

But there're about 161 GiB used on my Debian F2FS partition , it would take long time ...