Kinda. There are increasing numbers of hard dependencies on systemd components. And systemd components pull in systemd itself more often than not. So while in theory it’s optional, in practice it seems decreasingly so.
I tend to avoid systemd so I’ve taken to running Debian machines without it. But if you’re doing something like ephemeral cloud installations then it’s not “worth” the overhead of swapping out your init (and having the consequential reboot and potential instability) so the default is a required target for automation anyway. And if you’ve already set a target then why have another one?
This is why defaults can be harmful if widely deployed and considered non-optional (as systemd is on Debian). They become enforced by convention because they are the only valid common target without wrangling.
I tend to avoid systemd so I’ve taken to running Debian machines without it. But if you’re doing something like ephemeral cloud installations then it’s not “worth” the overhead of swapping out your init (and having the consequential reboot and potential instability) so the default is a required target for automation anyway. And if you’ve already set a target then why have another one?
This is why defaults can be harmful if widely deployed and considered non-optional (as systemd is on Debian). They become enforced by convention because they are the only valid common target without wrangling.