You're a bit behind the curve on this. EFI has been criticized for being horrendously complicated and gross since its inception.

Obligatory Matthew Garrett quote from a Linux kernel EFI patch in 2011:

UEFI stands for "Unified Extensible Firmware Interface", where "Firmware" is an ancient African word meaning "Why do something right when you can do it so wrong that children will weep and brave adults will cower before you", and "UEI" is Celtic for "We missed DOS so we burned it into your ROMs".

https://lkml.org/lkml/2011/5/25/228

Even on servers, I noticed that HP (now HPE) began locking access to server UEFI updates soon after http://lkml.org/lkml/2013/11/11/653 was posted.

The PC platform as a whole is going through a severe case of "second system effect".

Even back in the 1990s, there was ACPI. ACPI 1.0 for example dates back to the end of 1996 (of course before then there was drafts): http://uefi.org/sites/default/files/resources/ACPI_1.pdf But of course ACPI took years to catch on, during which low cost PCs from for example eMachines was coming.

I seem to recall Torvalds having some less than kind words about ACPI.

I know. In fact, there is a reason I wonder what would have happened if Intel bought Compaq back in 1991 with Rod Canion and Jim Harris staying on.