/etc/pacman.d/gnupg/gpg.conf is not updated
Many Parabola systems (including winston) have an old
/etc/pacman.d/gnupg/gpg.conf with the following content:
no-greeting no-permission-warning lock-never keyserver-options timeout=10 keyserver pool.sks-keyservers.net
Instead it should have that:
no-greeting no-permission-warning lock-never keyserver-options timeout=10 keyserver-options import-clean keyserver-options no-self-sigs-only
gpg.conf should be updated.
I've no idea if it's a bug in Parabola or Arch Linux though.