I don't find this question nasty/cynic or anything. I value your constructive comments. You have a valid point here.
Shipping a workstation with 10 GB max space would make users wanting to exceed that limit complain. They could grow the virtual hdd size (https://www.whonix.org/wiki/Grow_Virtual_Harddisk) but that is rather cumbersome and complicated due to missing easy GUI access to the required functions.
Operating system's / rsync / browser issue is:
They don't support sparse files well.
gzip's issue is:
It doesn't support sparse files. (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=535987) And I should not have taken gzip for that reason in the first place. (Took gzip, because it can produce deterministic archives.)
KVM's issue here is:
KVM has no alternative to VirtualBox's .ova feature. If they had one, we would not have to have this discussion. That's why we have to compress them.
The new compression method will be:
--mtime="2014-05-06 00:00:00" \
--file "$WHONIX_BINARY/Whonix-Gateway-$version.qcow2.xz" "Whonix-Gateway-$version.qcow2"
Which produces a deterministic sparse archive.
You can then unpack using:
tar xvf Whonix-Gateway-8.2.qcow2.xz
unxz won't work!)
And will end up with a spare image. Apparent size 100 GB, can grow up to 100 GB space, but will initially take no more than ~2GB space after extraction. I will re-compress, sign and upload soon.
You could still say you preferred non-compressed smaller 10 GB images that must be grown to take more than 10 GB? You would still have a point. In an ideal Whonix distro world, we would offer both types of images. In an ideal world, other projects would solve their issues with sparse files. [Best would still be, if KVM added an alternative to VirtualBox's ova feature.]