This, I think, gets at why I don't want to acknowledge "true" and "false", because it seems to me the only way to salvage those terms is to make them teleological to the purpose of likelihood of matching experiences of reality.

This is at least very close to what I meant. Consider this situation: you are walking along, and you see a man in the distance. "That looks like a pretty tall fellow," you say. When he approaches you, you can see how tall he is. Was your statement true or false? It is obvious that "pretty tall fellow" does not name a specific height or even give a minimum. So what determines whether your statement was true or not? You will almost certainly say that you were right if you do not find yourself surprised by his height compared to what you expected, or if you find him surprisingly tall, and similarly you will say that you were wrong if you find him surprisingly short compared to what you expected.

I guess this is fine but it's not really what most people mean when they say "true" and "false" as far as I can tell

But what do you think people really mean instead? I think pretty much everyone would agree with the above example: you are mistaken if you are surprised in the wrong direction, and you are right if you are not surprised, or if you are surprised in the right direction.

I suppose theoretically someone could say that truth and falsity mean that there is a bit somewhere in his metaphysical structure which has the value of 0 or 1, in such a way that "he is tall" is true if the bit is set to 1, and false if the bit is set to 0. But it seems obvious that this is not what people would normally mean at least when talking about this situation, even if they might sometimes say abstract things that sound sort of like this. And people will sometimes explicitly assert that there is something like such a bit in a particular case, e.g. whether or not something is human. This assertion is almost certainly false, but it is not some special kind of falsity about the existence of truth and falsity; they are simply mistakenly asserting the existence of such a bit in roughly the same way someone is mistaken if the person called tall turns out to be 4'11'.

So I don't see how people mean something different from this by truth and falsity, or at least significantly different.

so it seems better to reject the notions of "true" and "false" to avoid confusion about what we're discussing.

I think that doxastic voluntarism is true in general, but even if it is not, one aspect of it certainly is: we can use words to mean what we choose to use them to mean. And insofar as this is a matter of choice, practical considerations will be involved in deciding to use a word one way or another. You are pointing to this here: what benefit would we get from using "truth" in the above way, compared to using it in other ways?

I think most people will take the denial of truth to be a denial that the world is real. As I said earlier, if anything seems like a denial of realism, the denial of truth does. And most people, coming to the conclusion that there is no truth, will conclude that they should not bother to spend much time thinking about things. Obviously you haven't drawn that conclusion or you wouldn't be spending time on Less Wrong, but I think most people would draw that conclusion. So for someone who thinks that thinking is valuable, rejecting truth does not seem helpful.

In terms of avoiding confusion, you may be seeking an unattainable goal. The ability to understand is in a way limited, but also in a way not. As I said in another comment recently, we can think about anything; if not, just think about "what you can't think about." But this means we will always be confused when we attempt to think about the things on the boundaries of our understanding. Your visual field is limited, but you cannot see the edges of it, because if you could, they would not be the edges. In a similar way, your understanding is bounded, but you cannot directly understand the boundaries, because if you could, they would not be the boundaries. That implies there will always be an "edge of understanding" where you are going to be confused.