@freemo Methodical as he was, I think Tolkien also very much wanted to depict certain mysteries as essentially unknowable, for deliberate literary effect. In that sense, I believe Tolkien meant for Bombadil to be, in his deepest nature, someone about whom the reader is invited to speculate endlessly, but in such a way that no single and definite conclusion will ever be entirely satisfactory. See https://dc.swosu.edu/cgi/viewcontent.cgi?article=2896&context=mythlore
@freemo I’m not disagreeing with you, but the paper I linked includes a few quotes from Tolkien’s letters that may be of interest, even if you don’t want to read the whole thing