Of course, there are many other pretty good reasons to go with EFI. It's just that its fate seemed tied to that of Itanium back then.
Widely held by whom? The absolute simplest thing for Apple to have done at the time would've been to have kept using OpenFirmware, for maximum compatibility with existing PowerMacs (OpenFirmware boot code is written in platform-independent Forth).
This would've made building hackintoshes much harder than EFI, since EFI motherboards were quasi available at the time and clearly going to be growing in the future, whereas OpenFirmware x86 motherboards were speciality hardware that only Apple and Sun would have been producing.
The decision to use EFI is most easily understood as a compromise between retaining some of the abilities of OpenFirmware, avoidance of 30-years of unnecessary BIOS cruft, and a desire to enable people to run Windows, which EFI BIOS compatibility could enable but OpenFirmware could not.
Seriously, it's 2004-2005. You have the opportunity to define an x86-based platform from scratch. You'd like Windows compatibility as a business selling point, but you're sane so you don't want to chain yourself to a kludge like the PC BIOS in your own code base if you don't have to, because backwards compatibility isn't a concern.
EFI is the only obvious choice.
So now Apple has to support an EFI version no-one runs, while integrating Intel reference code targetted at newer versions to support new chipsets.
Well, it ensures job security for Apple's firmware engineers.