If their prejudices are that bad then they will border on xenophobia not just disinterest, then they very well may give into them. As many posters have brought up, they're trying to make richer characters by giving them back round information to grant them more human-like qualities. They had already had people attempt to kill you over using apostate magic after you rescued them ala rescuing the Tower of Mages if you're using non-sanctioned magic in front of Wynne. There's also several portions in the first game that were cut from the original where you can turn Morrigan over at your leisure if you consider apostates that dangerous. The dwarves had to have their dirty laundry pretty much dragged through the streets in DA:O if you weren't a dwarf before they'd listen to anything you had to say. You are even allowed to betray the Dalish elves to the werewolves if you so desire and the game itself plays on your sensibilities even more if you're a human PC because there are no elven or dwarf werewolves.
In DAII, the Dalish elves also refuse to assist Hawke in various situations until you bring Merrill along so there's definitely extreme tensions among the species already present in the world to the point of complete mistrust.
If the characters you're dealing with are that bad then you may have a situation like that on your hands. So it doesn't just become a question of race-gating at that point, it becomes a question of how far are they taking their hostilities towards other races, will they simply be sexual preference or will they be game changing enough to warrant a betrayal and slaying a now no longer companion?
You seem to forget that mages aren't a race. One of the points you bring up was cut content, which is ultimately meaningless. As far as we know, there isn't any class gating. I don't know what you're talking about with the Dalish in DA2, since I never had much trouble with them even if I didn't have Merrill with me. Your point about the dwarves is so ambiguous I'm not even going to address it. As for the Elf/Werewolf decision in DAO, your character could have had any number of reasons for why they did what they did.
There may be racism in the world, but it doesn't mean that you can't make the companions your friend if you try hard enough. It has always been that way in Dragon age. If you're willing to put in the effort, you can have a decent friendship even if you and the companion don't always agree. I can't recall any Bioware companion who will just automatically betray you based on race. If they turn on you, it's because of your own actions or lack thereof. You seem to be dead-set on dodging the issue here.
Retour en haut
WAAAAH!!! 
creeps away......I didn't do it....
