Unable to update Xcode

I'm trying to update Xcode from App Store, but it keeps complaining that there is not enough disk space. According to App Store description, Xcode size is 12.7 GB, but according to Finder's status bar, I have ~26GB available which I can confirm with "df" command in my Terminal as well:

$ df -h
Filesystem       Size   Used  Avail Capacity iused     ifree %iused  Mounted on
/dev/disk1s5s1  233Gi   14Gi   25Gi    37%  500632 257198320    0%   /
devfs           335Ki  335Ki    0Bi   100%    1158         0  100%   /dev
/dev/disk1s4    233Gi  1.0Gi   25Gi     4%       1 257198320    0%   /System/Volumes/VM
/dev/disk1s2    233Gi  635Mi   25Gi     3%    4751 257198320    0%   /System/Volumes/Preboot
/dev/disk1s6    233Gi  4.3Mi   25Gi     1%      20 257198320    0%   /System/Volumes/Update
/dev/disk1s1    233Gi  192Gi   25Gi    89% 2443410 257198320    1%   /System/Volumes/Data
map auto_home     0Bi    0Bi    0Bi   100%       0         0  100%   /System/Volumes/Data/home

Can someone maybe explain why is this happening and how to properly update Xcode? Thanks!