Josh Triplett wrote:
If the goal here is to hide the boot messages by default, note that
the default kernel command line includes "quiet", which hides most
kernel messages and systemd messages.
Note that the hiding of systemd messages is unintentional, and can make
debugging a system that fails to boot challanging. #718038
I asked the systemd maintainers to not make it overload quiet to do
that, but they don't want to, so if systemd continues being used in
Debian (even if not as default), d-i will need to start adding
systemd.show_status=1 to the kernel command line.