[avhception]

While individual implementations may or may not have had horrible bugs or consisted entirely of hacks, I think just carrying forward the expectation of having a proper, all-powerful text prompt into the firmware that can easily be made accessible remotely would have been a real boon to the foundations of server hardware. With time, the bugs could have been fixed and the hacks replaced with proper implementations.

[spijdar]

I think this boils down to a cost problem more than an engineering or cultural one. If you look at the original Itanium machines of the early 2000s, they had BMCs like the Sun ones, and they ran EFI as the base firmware, often with no graphical head. Pure serial!

There's no reason you couldn't build a solid, headless PC-compatible architecture based around EFI. It would just... cost money. Even in the retrocomputing stuff you see the same thing happen. Older VAXes had very rich boot PROMs, but by the time you get to models like the 4000 "Very Low Cost", most functionality was stripped out of the PROM to save space and cost.