Queer was a slur within living memory [1] - it's been largely reclaimed in the last few decades, but it's still offensive to some. You'll find that when respectable publications use the term, it's always in a positive context.
When it comes to LGBTQ it's not offensive - much like one can refer to legendary gangster rap group NWA by their chosen abbreviation, even if the N stands for a word you wouldn't use in polite company.
It used to be a slur, then the community adopted the word as their own. That historical negative connotation still lingers for those who remember it that way, though.
I think that the word "queer" has been used for a long enough time in neutral to positive contexts, including official. I won't see it as an offensive word by itself. It's similar to what happened to the word "geek".
The 'N' word has seen a similar adoption and "historical negative connotatione still lingers for those who remember it that way" as well. I doubt they'll allow that particular slur however(and rightly so).
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.
You can claim this about any non-slurs too. I actually would argue that most sites don’t do any kind of blanket ban, perhaps social sites. Queer as a slur has American roots. Most of the world doesn’t acknowledge such illogical frailty.
