Edit for the moderators (and anyone who cares)
What I have here is a suspicion, actually shared by a number of important intellectuals and other less known people, thus not exactly a 'personal philosophy', but a real inquiry. I have given lots of references for that. My question is why most people don't seem to agree, or even see, that point of view, since it looks so clear to many of us, and also if any respected intellectuals have addressed the question or not. This is totally different than just asking if I'm right or wrong, as you imply. As some have noted, this close is looking arbitrary and political, more than anything else.
In a recent decision from the Brazilian Committee for Biosafety regarding the approval or not of a certain transgenic seed, I've read the delegates votes and their reasoning. Actually, the only one who presented any reasoning was the only vote against the approval. In three pages, the delegate presented a list of reasons why he thought that seed wasn't safe enough for mass production. All other delegates (about ten) just voted in favor of approval, without at least arguing why they thought the other delegate was wrong. You don't need to do this in Postmodern times. "Each one has its own truth", so what's the point in debating? Postmodernists don't see any sense in trying to reach consensus. I'm not sure if the ten delegates received any money to help them decide their votes (what is probable), the biggest problem is that they're allowed to vote without explaining their reasoning (what's scandalous, since there were strong reasons to vote against the approval). This "death of reason" is the utmost tragic consequence of Postmodernism.
That Postmodernism is indeed harmful to the Left is something very few people have noticed in its early days, but now in Trump's era it's becoming more and more evident.
The number of critics against Postmodernism is not only huge, but many also come from very respected intellectuals. When Derrida earned an honorary degree in Cambridge, for instance, some of them (including Barry Smith, Hans Albert, David Malet Armstrong, Ruth Barcan Marcus, Willard Van Orman Quine, Peter Simons, René Thom, among others) signed a letter of protest, where we can read (emphasis mine on this and next quotes):
Many French philosophers see in M. Derrida only cause for silent embarrassment, his antics having contributed significantly to the widespread impression that contemporary French philosophy is little more than an object of ridicule.
(...) Many have been willing to give M. Derrida the benefit of the doubt, insisting that language of such depth and difficulty of interpretation must hide deep and subtle thoughts indeed.
When the effort is made to penetrate it, however, it becomes clear, to us at least, that, where coherent assertions are being made at all, these are either false or trivial.
Academic status based on what seems to us to be little more than semi-intelligible attacks upon the values of reason, truth, and scholarship is not, we submit, sufficient grounds for the awarding of an honorary degree in a distinguished university.
And consider Chomsky's point of view (video, transcription):
It's all very inflated, you know a lot of prestige and so on – it has a terrible effect in the Third World [this part just can't be stressed enough]. In the First World, rich countries, it doesn't really matter that much. So if a lot of nonsense goes on in the Paris cafés or Yale comparative literature department – well, okay. On the other hand in the Third World, popular movements really need serious intellectuals to participate. And if they're all ranting postmodernist absurdities... well, they're gone. I've seen real examples – could give them to you.
But – so there is that category. And it’s considered very left wing, very advanced. Well, some of what appears in it, actually makes sense. But when you reproduce it in monosyllables [legible text], it turns out to be truisms. So yes, it is perfectly true that when you look at scientists in the West, they’re mostly men. And it’s perfectly true that women have had a hard time breaking into the scientific fields. And it’s perfectly true that there are institutional factors determining how science proceeds that reflect power structures. I mean ALL of this can be described literally in monosyllables, and it turns out to be truisms when you look at it. On the other hand, you don’t get to be a respected intellectual by presenting truisms in monosyllables.
Consider how Postmodernism has been used by the Right-wing recently (examples here, here, here, here and here), despite most still seeming to believe it's a "Left-wing movement". Of course, that's nothing new. Consider, for instance, Benito Mussolini's quote:
If relativism signifies contempt for fixed categories and those who claim to be the bearers of objective immortal truth, then there is nothing more relativistic than Fascist attitudes and activity. From the fact that all ideologies are of equal value, we Fascists conclude that we have the right to create our own ideology and to enforce it with all the energy of which we are capable.
Or this one from the great historian, Eric Hobsbawm:
Nevertheless, in some ways I had lost touch with many of the currents of French culture and theoretical discussion after the 1960s, and, although any admirer of Queneau and Perec cannot but be sympathetic to the French intellectual tradition of playing games with language, as French thinkers increasingly moved into the territory of ‘postmodernism’ I found them uninteresting, incomprehensible, and in any case of not much use to historians. Even their puns failed to grip.
Better yet, we can go back a few centuries and recall Schopenhauer's words:
If a man is capable of thinking anything at all, he is also always able to express it in clear, intelligible, and unambiguous terms. Those writers who construct difficult, obscure, involved, and equivocal sentences, most certainly do not know aright what it is that they want to say: they have only a dull consciousness of it, which is still in the stage of struggle to shape itself as thought. Often, indeed, their desire is to conceal from themselves and others that they really have nothing at all to say.
I have pointed out some other critics elsewhere. But what really bugs me is how many philosophers (and philosophy students) insist in seeing nothing wrong with it. The question is: why? Haven't they thought enough about it, and just assume that such a great and fashionable movement "must be right"? They see in it an opportunity for their own individuality and lack of interest in the "greater good"? Have they thought enough, and really believe Postmodernism is the way to the "greater good"? Are they far enough from the "third-world" so as not to see what's going on there? Had any philosopher published his honest views on this point?
PS: All these questions apply not only to philosophers and philosophy students, but also to the users and moderators on this site.
Note: Six hours after the question was posted, with 400 views (a personal record), it had 3 votes for closing. Like I said, the Right hates questions about the reality of facts, accepting only questions that allow the students to display the endless hours of reading about texts that not always are useful to society. What a shame! (For comparison, this other question, related, had only 95 views in 3 days...)
EDIT
As you can see from the personal account below, one doesn't have to write (or think) like postmodernists to realize that there's something utterly wrong in "philosophy" courses (and this site). I wouldn't wonder if all moderators here are Caucasian Western men, full of bias against anyone else (and still defending Postmodernism...).
So, fairly early in my career as a PhD student I learned that certain ways of doing philosophy are acceptable, while others are not. Likewise, certain topics count as legitimate philosophy, and others do not. These disciplinary boundaries, by and large, are not up for debate.