Many people use some form of manual fumbling configuration management to create or manage content of remote machines’ ~/.ssh/authorized_keys files, and whether it’s the likes of Chef, Puppet, Ansible, or your particular poison, the principle is the same: SSH public keys are copied into static files on the target systems. This works very well and is a well-understood technology. (At this point I’ll remind of the existence of ssh-copy-id, likely easier and less error-prone to use than man...
