That’s not a spurious binary, and in any case it doesn’t make the disjunction wrong. Observe:
Let P = “Alice meant exactly what it seems like she wrote.”
¬P = “It is not the case that Alice meant exactly what it seems like she wrote.”
And we know that P ∨ ¬P is true for all P.
Is “It is not the case that Alice meant exactly what it seems like she wrote” the same as “Alice meant something other than what it seems like she wrote”?
No, not quite. Other possibilities include things like “Alice didn’t mean anything at all, and was making a nonsense comment, as a sort of performance art”, etc. But I think we can discount those.
That’s not a spurious binary, and in any case it doesn’t make the disjunction wrong. Observe:
Let P = “Alice meant exactly what it seems like she wrote.”
¬P = “It is not the case that Alice meant exactly what it seems like she wrote.”
And we know that P ∨ ¬P is true for all P.
Is “It is not the case that Alice meant exactly what it seems like she wrote” the same as “Alice meant something other than what it seems like she wrote”?
No, not quite. Other possibilities include things like “Alice didn’t mean anything at all, and was making a nonsense comment, as a sort of performance art”, etc. But I think we can discount those.