Structural Data at Inline Level an afterthought?

To be clear, this is in no way meant to be rude or offensive, just a question.

One of the project's advertised core feature appears to be the ability to get clean JSON data for a document. This is certainly true at the block element level. At the inline-level though it appears to be wild-west with everyone happily adding HTML tags to the resulting JSON data in order to achieve basic styling like bold, italic, foreground color etc.

Which leads me to the question, whether the whole data structure wasn't really thought through at the design stage of the project?