Its part of ALPM.
They are not expected to do anything with $HOME.
Software or users OK, but packages no.
It may be illustrative to note that those paths are populated by the applications .. like firefox being launched creates the ~/.mozilla folder.. the firefox package does not.
Disagree.
The packages have nothing to do with files in your $HOME and should not.
Not really.
It has no concept of packages, nor does it search your $HOME for ‘old’ folders or similar.
The closest it gets is ~/.cache I believe as well as some specific application support like FF and VLC.
There is my thing but again it only supports so much.
Ultimately what happens in your $HOME is up to you, as it should be.