Unfortunately, there's plenty of vendors that suck at writing firmware, and most usually give up on updating it immediately after they've EOL'd the hardware revision. The hackintosh project mostly works by replacing the bugs from the vendor firmware into the bugs that apple expected from their x86 line of pcs.
If most vendors suck at writing firmware, it might be a problem with the spec though.
If most vendors suck at writing firmware, it might be a problem with the spec though.