Dreaming of Post-Queer Times

I agree with a lot of the points made here (i.e. that the comment was kind of presumptuous, that a vision of a "post-orientation" culture is kind of naive, that there's an implied of erasure/assimilation of some underlying subcultures). But I do sympathize with the idea of relying less on these labels, because they do tend to have some unfortunate effects on people who are in-between, or not covered by, the common labels.
Probably there are other examples, but in my life there were some problems with the questioning phase and coming out as bisexual. When I was young and questioning, if someone asked if I was straight or gay, it was easy to say "I'm straight", harder to say "I'm questioning" (because of the implication of immaturity and because of people wanting to "help you choose/figure it out"), and hardest of all to have the self-awareness and honesty to say, "I don't know, I find all kinds of people interesting, but it seems socially and statistically easier to focus on women for now". When I came out as bi, it was easiest (if frustrating) to let people have their misconceptions, harder to correct them (no, it's not the same as being polyamorous, no, I'm not just trying to pretend I'm not gay), and hardest to just be blunt and say "Seriously, I haven't had some kind of personality transplant, I'm just the same person except that now I'm acknowledging that I like men too."
This is aside from the irrelevant distinctions and weird claiming behaviors that happen. I had a straight guy patronizingly "remind me" that I shouldn't be annoyed by anti-gay slurs because I'm not technically gay (so many things wrong with that…). I've been told that the way I'm interested in women "really isn't the same" as how straight guys or lesbians feel, from someone who knew almost nothing about me or my past relationships. People who said they wouldn't date "someone like that" because they'd be afraid of cheating. My point here isn't to go through the whole litany of stuff that happens to bisexuals. The point is that a lot of these people were perfectly capable of learning the lesson "Gay and lesbian people can have emotions and habits that aren't totally different from straight people's." And they were perfectly capable of learning the lesson "Just accept it when people say they are gay or lesbian, rather than trying to second-guess them or change their minds." But the moment you threw in a new label, for some reason they had to relearn all the same things about a "totally new" group they hadn't thought about, even when there was nothing truly new to learn there.
Of course, some people do express themselves very differently after they come out, partly because they can feel more open (I'd guess that this is especially true for gender identity). And (admittedly without a very broad perspective on the matter), I'd think that it can be very helpful to be supported during those changes, which people might be better at doing if they have a label that helps them understand what changes, exactly, are going on. I'm just bothered when in some people's eyes you've suddenly turned into an alien being from a distant culture because you changed labels (as Besomyka says, "othering").
So I guess my concern about labels is the essentialism that sometimes comes with them. A world that makes fewer assumptions, that asks more open-ended questions, in which you don't always have to "come out" as a specific thing but merely live it, might allow more room for people to do what they like, explore what they like, and not worry about what kinds of judgments or confusions might happen because of one very generic word. Whereas a world in which everyone has to choose a label (or have one applied for them) is one in which "coming out" is like asking people to take you out of one box and put you into another box. Which makes things easier if you do fit more comfortably in the other box, and harder if you don't.
I don't know if there's an easy answer here at all. Maybe there is no way to reduce labelling beyond a certain point without threatening diverse identities. But I think that they are two different issues to some extent: on the one hand, having diverse communities, and on the other, framing the way each individual lives in terms of group membership.
(Addendum: Naturally there are similar questions that arise outside of the "queer" umbrella. Issues of multiracial, subcultural, and immigrant identity can raise the same issues.  To use myself as a self-centered example again:
Am I white because of I look white, and because of the social/economic privilege that comes with having light skin color and growing up in suburbia? Hispanic because of our convention of hypodescent, my last name, the influences of my father's family and school's mostly Latino neighborhood, and because my father lacked the aforementioned privilege? Multiracial because of the difference in my parents' culture, heritage, and skin color, because of my actual genes, and because it's a catch-all group? White Hispanic because I look white but have Hispanic heritage? Non-white Hispanic because of hypodescent and because it's the category I'd be under for assessing medical risks? Should I broaden this to the increasingly common "Latino", narrow it to "Mexican-American" (in the 3rd generation?), or stick with the "Hispanic" self-description my dad's family always used? Should I take my brother's experiences into account? Cousins? Weigh our barbacoa against our barbeque? Our privilege against our deprivation? Immigration statuses and cultural identifiers? Does my small, distant amount of Native American ancestry on my mom's side matter at all, so many generations later?
Are some of these labels ones I shouldn't use because they are wrong or deceptive, or do I have the moral right to identify however I want? Is it better to try to be a visible Hispanic person working in science to undermine stereotypes, or is it silly or inappropriate to say that about someone with blond-ish hair who isn't much of a target for discrimination? Would the answer be different if it was "black" versus "white", race rather than ethnicity? Can I change my answer on a whim? Should I declare that there is no generic answer and never will be, because race and ethnicity are socially constructed and there's no one sensible socially constructed answer? Then do I have to leave those checkboxes blank on surveys? What will my kids or nieces or nephews check, if I ever have them? What if I move to another part of the world?
These identity labels may be useful in many situations, but sometimes they confuse more than clarify, and it's even harder when I have ambivalent and varying feelings about how to self-identify. From a purely rational/philosophical perspective, the mistake here is to assume that everyone has a label for each type of social classification, and that no one has more than one or two.)