Revan was supposedly dead by then, remember? Killed after Bastila and a small Jedi strike force boarded his Dreadnought, which coincided with Malak trying to blow it up to smithereens.
Your purpose on the original KoToR, after departing Taris and receiving Jedi training on Dantooine, was to discover the location of the Star Forge, which was the never ending glory crafted by the Builders, and stop Malak in the process.
True, but he also started the Jedi Civil War. The whole point was to help stop what he created, which was the war and Malak. The Starforge was added after you figure out how Malak was creating his army, it wasn't the driving force at the beginning.
In either case, it really doesn't matter. People lived Revan's story. I for one picked him to be a Sith. But I don't feel cheated by the change. We all knew that they would have to pick an ending. Such is life. That for me doesn't break any of the connection I had with the character.
But to each their own. The point here, as it's really easy to figure out why people like Revan.