Yes, this is quite an interesting feature of philosophy, and I would say, an interesting feature of the world: that some opinions are more valuable than others.
Nietzsche's argument against the existence of God has become a common argument against any and all truth. Zarathustra tells his disciples: "If there were gods, how could I stand not to be a god! Therefore there are no gods."
Poor Plato, it seems the only sin of which he is accused, and for which he is pilloried, is that of having lived a long time ago. But for all of the comments, I can find no arguments against any thesis in Plato. And this is noteworthy. Not just because it indicates that Plato is here just a straw man and that few (if any) of his assailants here have read him, and so of course, have no grounds to criticize. But more importantly, because, Plato does not have some set of theses which even could be toppled or made irrelevant. Plato does not work like that. Philosophy does not (usually) work like that. Plato does not promulgate, he investigates. He is still taught not so much because his answers are still relevant, but because his questions are. The original article implicitly acknowledges this point when the author guesses that philosophers trained in "modern" disciplines might "get farther" than Plato on the big questions—to which one might reply: and how shall they know the big questions?
Someone here pointed out that this wholesale dismissal of philosophy is a category mistake (a welcome reference to Aristotle), and I agree. If you will forgive my speaking too broadly, the difficulty many non-philosophers seem to have with philosophy is simply that they do not know what it is—and more importantly, that they have never done it. I do not fault them for this (and I'll readily admit that our academies are very much at fault here, as the professionalization of philosophy has done no favors for philosophers or non-philosophers) but one ought to have, if not enough humility, at least enough love for truth to motivate silence, study, or wonder in the face of the unknown—not slander.
Philosophy (and especially Plato's philosophy) is not the sort of thing for which one uses a textbook. If you recall the Phaedrus (and if you don't recall the Phaedrus, you probably should not be commenting on philosophy) you'll remember that Plato has an argument against books. He worries that books will codify doxa in such a way as to stifle inquiry—a worry that was clearly warranted, as evidenced by this thread. Thus he preferred dialogues to dissertations, and precisely because the individual appropriation of knowledge, and the harmonizing of the person with reality, is what really counts—not knowing (or believing) a bunch of stuff. It is important to remember that Plato, even when making myths, is imminently and always practical.
Those who advocate that contemporary science is better equipped than philosophy to answer the big questions, because science "examines reality, etc." fail to recognize that "reality" itself is big question. In my own experience, I have often found it amusing how quickly some "scientists" dismiss philosophy, while I've met very few philosophers who would do the same for science. It is fine if one wants to ignore philosophy, but it is hubris to dismiss it simply because it does not do what one wants it to do.
Nietzsche's argument against the existence of God has become a common argument against any and all truth. Zarathustra tells his disciples: "If there were gods, how could I stand not to be a god! Therefore there are no gods."
Therefore do not study philosophy.