How is the literal phrase “Lariska is the size of a Toa” not a strong canon imposition?
Saying that the post shouldn’t count because Greg forgot about it nearly a decade later is completely meaningless; if we were to decanonize every detail that Greg forgot by now, half the canon would be gone (and that goes for the novels as well, not just Greg Quotes).
Ultimately, none of this matters for the MOC that started this discussion (or any Lariska MOC), since there are no canonical size limits being imposed. The fact that Lariska is Toa-sized in-universe will have no bearing whatsoever on which entries are or are not allowed.