I disagree. In the Masked Empire, at least, the elves of Halamshiral revere their Dalish counterparts, and will often run into the Dales in the hopes of escaping to join the Dalish, so I'm not seeing that much xenophobia from City elves. Neither am I seeing any magophobia against the Dalish either, since the City elves have their own apostates as well.
Well, to be honest, only two City Elves mention the Dalish at all. Once when the owner ot he burnt building describes Felassan to Gaspard and the other one was in Halamshiral... talking to Felassan himself, angry that they were going to kill one miserable noble instead of helping the rebellion more. It's Briala the one who almost worships the Dalish, only to discover that they were as flawed as everyone else in the crappy Thedosian world.
A better proof of less xenophobia among City Elves would actually be the presence of humans born of elven mothers in the Alienage. When Lemet (a city elf in Halamshiral) suggested a friend could be in trouble when talking about the Dales (not the Dalish, mind you), Thren mentioned that the tavern was full of elves so there was no problem. When Lemet silently pointed out that there were others too, Thren said:
"Fine. A few flat-ears, but you know what I mean. You're going to blame Gestan and Thale because their mothers got friendly with some noble and popped-out a half-blood? It’s not like they get to live in the nice part of town just because they look human. Nobody in there is going to carry tales back to the nobles about the elves talking about back when they ruled this city."
It seems that for City Elves the most important thing is that their neighbours share their fate. That would explain why they don't have (many) problems with half-bloods or Dalish living among them in the alienages.