"YOUR MANNER OF ARGUING IS JUST TO POST A LOT OF TEXT UNTIL THE OPPOSITION GIVES UP."
Or some variation of this. Probably the most common being a simple "WAH WAH WAH TOO MUCH TEXT NOT SMRAT ENUFF 2 REED TWO PARAGRAPHS."
(For the sake of simplicity, the person who uses such an argument will be referred to as Person A, whereas the accused person will be referred to as Person B.)
The problem with this is that it's logically unsound and is an obvious strawmen argument, meant to divert the attention of the opposition rather than address their points. And it's pretty obvious that if a person is responding to an argument, yet isn't actually addressing the points -- they have nothing to come back with.
If Person B were to unload an onslaught of empty words with no substance, then perhaps such a statement would be warranted. The inconsistency lies in relevance. If Person B's responses are relevant and are simply Person B responding with enough information to formally combat all of Person A's claims -- then it's simply a matter of covering one's bases and countering all platforms in the argument (which is the way one should approach any debate.)
By covering one's bases and ensuring that their argument is logically impregnable, it demonstrates that Person B has actually given thought (I know, such a horrible thing to do in a debate, right?) to the topic at hand instead of relying on defense mechanisms to wringle out of addressing the points (hint, hint, Person A.) All in all, that means that Person B cares more about being right than appearing right or convincing themselves that they're right.
Ironically, such a statement (which, lets be honest, is a stonewall tactic) by Person A pretty much seals their fate in the debate (ha! That rhymed!) This is done because what Person A essentially says is that they have not given as much thought to the subject as Person B, thus cementing that they're out of their league. You may as well declare victory as soon as someone uses a smokescreen argument like this because what they're telling you is "You know far too much about this subject and I will look bad by comparison if I try to tackle it all." That doesn't mean you're right; it just means you won the debate because your opposition isn't smart enough to refute what you're saying.
That's not to say that you should intentionally try to make long winded arguments. Just say what is relevant. If it's long, then it's long. But be mindful not to confuse a broad range of thought culminating in a lot to say with filler. Such an argument would have to take the stance that all books, articles, et cetera... are just using filler to stifle discussion, rather than the more reasonable notion that it's a broader subject than duuuuuurrrrr 2+2=4. Some things are just broad subjects. Simple as that.
Some may call you out when you have a lot to say and you're saying a lot. Claim it is, indeed, filler. However, the simple solution to countering such an argument is to demonstrate how it is, indeed, filler and not relevant to the conversation. If it is filler, then it won't be able to stand the test of scrutiny. If it's not, then they will be unable to explain it and likely dodge the question all together.