Lexicus
Deity
For the simple reason that the author is not speaking objectively on their own works or intentionality, but is rather speculating on the intentionality of a past version of themself. That speculation will always be distorted - by time, memory, context, hindsight, and so on. In the same way that we can misremember things from the past, or color them differently - take for instance a thing you enjoyed or were proud of in the past which you now view as cringe, or a with a certain nostalgic quaintness. The same applies to an author of a text.
This whole thread has been very silly. The people bringing forward that quote from Tolkien about how he despises allegory and had no intention of any of his work being made into allegory as if to foreclose any metaphorical interpretation of his work is ludicrous. Meaning in language is not fixed. A text's meaning and intention can exist independent of an author's own intent - even in that author's radical absence. Therefore, to hold an author's intent - whether stated or inferred - as sacrosanct, as the final word on a text's absolute meaning, is, I think, a rather sad and myopic way to interact with art and language. Great texts lend themselves to multiple interpretations. Lord of the Rings is no different.
I agree with this point about the death ofthe author, but I would just add that in the particular context of the quoted post, "the man's own words on the subject" were quite unambiguous:
"The dwarves of course are quite obviously, wouldn't you say that in many ways they remind you of the Jews? Their words are Semitic, obviously, constructed to be Semitic."
And again:
JRR Tolkien, letter 176: "I do think of the 'dwarves' like jews".
In any event the point of bringing up this parallel was actually to defend Tolkien against an accusation from the OP of this thread that Sauron was meant to be Jewish, which is an idea I have never encountered before (whereas the Jewish-Dwarf connection is well-known and has been written and commented on by many authors including JRRT himself).