Thinking the opposite is fine by me, but without giving out another argument is unfair, at this point you might try reconsidering your posture about Tom Bombadil, you posture which is "might be", something points as tom bombadil been a nature spirit and pretty logical and literal hope you find it.
I don't necessarily think the opposite. I think if you have to put a definition to Tom Bombail's character and his place within the cosmology of Tolkien's legendarium, then to me he makes more sense as an embodiment of one (or more) of the features of Tolkien's creation story. Whether he is an embodiment of the universe its self, an embodiment of Eru's ability to create (or at least bring into existence) or an embodiment of the music (which ties in very well with his constant habitual singing). While he is most certainly natural I think the phrase "nature spirit" applies too many limitations and connotations to him that don't fit with what is said about him, by himself or others. For him to be the eldest, for example, implies age or existence older and longer than that of any Valar. He was around before the Dark Lord came from Outside so he has at least been on (or in) Arda since before the Valar arrived. This is why I think he may be some "by product" of Eru's creation process. Tied to Ea and Arda, but not necessarily "of it" in the "nature spirit" sence. I think nature spirit adequately describes Goldberry (at least from what we know of her) so a union between the vague creation elements and nature being the union of Tom and Goldberry fits quite well in my mind.
Of course this is all speculation by fans and essayists - Tolkien put Tom Bombadil in because he wanted to.
I don't necessarily think the opposite. I think if you have to put a definition to Tom Bombail's character and his place within the cosmology of Tolkien's legendarium, then to me he makes more sense as an embodiment of one (or more) of the features of Tolkien's creation story. Whether he is an embodiment of the universe its self, an embodiment of Eru's ability to create (or at least bring into existence) or an embodiment of the music (which ties in very well with his constant habitual singing). While he is most certainly natural I think the phrase "nature spirit" applies too many limitations and connotations to him that don't fit with what is said about him, by himself or others. For him to be the eldest, for example, implies age or existence older and longer than that of any Valar. He was around before the Dark Lord came from Outside so he has at least been on (or in) Arda since before the Valar arrived. This is why I think he may be some "by product" of Eru's creation process. Tied to Ea and Arda, but not necessarily "of it" in the "nature spirit" sence. I think nature spirit adequately describes Goldberry (at least from what we know of her) so a union between the vague creation elements and nature being the union of Tom and Goldberry fits quite well in my mind.
Of course this is all speculation by fans and essayists - Tolkien put Tom Bombadil in because he wanted to.
You said something key about it, Golberry and Tombadil even if you analyse the mystery Tolkien put about it, nature is all around it, first he is married to the daughter of the river, he is the eldest and saw the first acorn, his enemy is Old man willow (other clue), he saw the dark lord come beyond.
All except last thing, give Tom Bombadil a nature base, he was there were only Trees were there in the primordial forest, he probably saw the dark lord (sauron) come from beyond or Morgoth either one of them fits, he is married to Gold berry daughter of the river which is (element water), Old man willow was one of the first trees along with Tom bombadil, as only the Valar or Nature Yavanna made ents, trees and acorns, huorns, etc. Its safe to assume she made Tom Bombadil and was given flame imperishable by Eru, just like dwarves and Aüle.