FFXII: The Zodiac Age is the very definition of remaster; not remake.
If you were only exposed to the US release of FFXII, I suppose I could see why you'd consider it to have elements of a remake to it. However, TZA isn't a remaster of the 2006 original game, but the 2007, JP-only FFXII: International Zodiac Job System. The significant bulk of the gameplay changes between vanilla and TZA are actually lifted straight from IZJS.
Oh, there were a few changes made for TZA. Some loot tables, drops, and gear were adjusted. The 9999 damage cap was lifted. The magick effects buffer queue was dropped. A second fast-forward option was added. And they upped the job count per character from one to two. They added some new OST options. They front-loaded the gambits towards the beginning of the game, to give you more tactical options sooner. The Sky Pirate's Den was cut out. But this is so close to IZJS, that you can literally pull up some FAQs and walkthroughs from the 2007 edition of the game and have no issues. (FAQs and walkthroughs of the 2006 Vanilla release are pretty much useless, though).