Hello,maybe it is documented somewhere and I missed it, but to disable password login on an ssh server it is not sufficient to specify UsePAM=no (which is the default) in /etc/ssh/sshd_config because it is enabled by the /etc/ssh/sshd_config.d/9999999gentoo-pam.conf, so you need to comment out 'UsePAM=yes' in there.
raf
