The big difference is that black people didn't "reclaim" the "N"-word slur, we always used it, it just doesn't mean the same thing when we say it to each other*. Now, the internet and the media spend a lot of effort to keep us from saying it.

In the case of "queer", it seems that even straight people somehow got to reclaim it, everybody is throwing it around, and that a large number of gay people don't like it at all.

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[*] Between black people it's usually more about telling somebody they're full of themselves. From white people to black people, empirically, it has almost always been followed with a murder threat.