I feel this is the kind of discussion that would really benefit from a number of concrete examples.
Not at all. Mainly because this is asking for the first line of examples, not repeatedly bogging down the conversation with constant requests for additional evidence.
Also it matters because in this kind of vague remarks that Wikipedia is unreliable, or that articles are wrong, almost always the people claiming this fail to provide specific examples, instead relying on some general feeling of frustration and shared belief that it must be true. But if they provided a specific example of a factually incorrect article, maybe other people would disagree. Or if they provided an example of ideological bias, maybe it would turn out the complainer is in the minority in believing that was biased. And if it turned out that this were controversial topics that most encyclopedic articles struggle with in some form, maybe it isn't a problem with Wikipedia. So examples matter!
You really believe that applies here?
Its hard to say its relentless when not a single piece of evidence has been given so far.
Its hard to say its tangential when it speaks to the original poster's thesis.
Nobody is actually showing us why the problem they choose to highlight is significant enough to torpedo Wikipedia altogether (or even that is a more important problem than all the others mentioned).
Also, nobody here is starting a long argument to waste people’s time. They’re simply saying “your one paragraph proclamation is completely unconvincing”.