If you are connecting movie disappointment with the love for a game character, you are approaching it wrong.
At least in my experience, Revan's history (before my PC made all the decisions) was steered by the "WHAT?!" moment towards the end of Act II to the game, where the character I heard bits and pieces about turned out to be me.
Keep in mind I played Revan as a male DS character so once I heard that I was the famed Dark Lord of the Sith who was destined to bring the Republic to its knees, I was ecstatic. I liked Revan because he was Revan; I was not and am not disappointed with Darth Vader's past and feel some tragic, ingrained need to fill some void in my heart with him and have no attachment to Revan as being the Darth Vader of my life.
Revan, for me as a fan of him while playing the game, was to be the fallen Dark Lord of the Sith who regained his lost glory, swept Malak's Empire from under him (along with his apprentice), and set himself back on his destined path to conquer the galaxy.
Now, respecting Revan as a male LS character with lore stretching from the EU onward, I respect Revan as a tragic figure who's life has been a struggle between the duality in human morality as he makes the more difficult (and sometimes outright wrong) choices in his life.
Revan fanboyism stems from simple an attachment to a character to an extremity. This ranges from nostalgia of the first game, Obsidian's hype of him in the second game, the player's choices and decisions as him, the literal assumptions from player perspectives in both games, the fact he believed in a balance between both sides of the Force (the "cool" thing to believe), and (my personal favorite
) him being the hero who played the villain for the "greater good."
Keep in mind the above mentioned range from being true, false, and/or misinterpretations.
That is how I see it anyway, imo.