Ah, the early Sun days
I remember those days where there desktop machines were really just mainframes / mini-computers that were trimmed down with the standard TTY and printer were replaced with a video controller and a keyboard. They'd go all weird weird when one of those wasn't working because the system never expected those things to not be available (what with them supposed to be soldered on...).
I also remember some of the models that tried to be smart and if a keyboard and/or monitor was missing at boot, the system assumed you are wanting to use Serial 0 as the console. So if you accidentally knocked out the keyboard at boot, the system would work just fine (OS would boot, daemons would start and begin doing their thing, etc), but nothing would be displayed on the console, nor would keyboard input do anything (Since the keyboard input is now routed to TTY1, but TTY0 is attached to the kernel).
A lot of it was just really teething issues and programmers needing to unlearn a bunch of assumptions from before the beginning of the transition from computers having their own rooms to them being out in the office.