"'I'm not surprised. You just told dnf that /home was its working
directory, so it can do whatever it wants with it. It's going to want
to clean it out so only the relevant files are there."
Sorry, I did not give dnf the right to delete files it did not create in
that directory. Note that it also wiped sub directories, which I did not
agree to.
Here is what the man page says:
" --downloaddir=<path>, --destdir=<path>
Redirect downloaded packages to provided directory. The
option has to be used to‐
gether with the --downloadonly command line option, with
the download command
(dnf-plugins-core) or with the system-upgrade command
(dnf-plugins-extras)."
No warnings about wiping other data !