I can say from my development, that console API extensions on XBox and in general the PS API allow you to intuitively reach creative constructions, which afterwards are a big PITA to somehow recreate on the PC APIs. The most interesting, and fairly easy to use parts, are often not available on the PC at all.
As a small example, the shared memory is very easy to exploit, and the internal organization of textures is fixed, the two together remove a large amount of processing. The PC is abstracting this organization, and has to, because from game-start to game-start you might change the card, or the driver. Ofc there's the possibility to say, that the organization is acessible/visible, and in exchange you have to manage it yourself, and rebake them when something changes. This is not available on the PC APIs, and it will never be, judging the stance and arguments from driver developers and MS personel.
There are many more, very in-depth programming involving cases, which can't be shared. Be assured that from a performance optimization perspective the two realms (console vs. PC APIs) are somewhat different universes for a programmer. And the consoles are not hard to program, like a long time ago, it's fairly easy and streightforward, if you know what you are doing.