In most distributions, OpenSSH's /etc/sshd_config has "Include /etc/ssh/sshd_config.d/*.conf" as the first line (and something similar for ssh_config), which allows using drop-in config files instead of editing the pacman-provided file, easily splitting configs for reuse between machines, etc. It'd be nice if Arch's openssh package implemented the same thing. This feature is available since OpenSSH 7.3p1 and not available as of the packaged version 9.3p2-1.

(This sounds like something that could have been requested in the past, but nothing relevant came up after a few searches and googling. Apologies if this is duplicated...)