... in the same precise way in which you would analyse written words. It doesn't work like that. When someone gives an interview, the words that come out aren't all that precise, and they're spoken in a particular context, in response to a particular question.

The context here is 'The Hobbit' - its relation to 'Lord of the Rings' and his adaptation of it - how he can make three films out a a single book. And in that context what he says is correct, as a broad outline of Tolkien's published fiction. The Hobbit came first, LotR was the sequel, and the Appendices, explaining and developing the background grew in the writing of that - and Tolkien did see inconsistencies between The Hobbit and the later work and he did consider rewriting. There is a lot of material in the Appendices which provides background information relating to The Hobbit.