I don't think such a section would get in the way of quickly getting started with a game (that's what the phb is for, after all). It's more just acknowledgement that the role of the dm is partially to facilitate the game for several people, and that's going to involve getting to know what those people want and don't want out of the game.In days of old, provided at least one person had the books, IME* games and campaigns could and did start among friends almost on a whim. Roll-up was relatively simple (and considered part of play rather than almost being its own sub-game) and off it went from there.
* - and in the anecdotal experience of others, beyond just our crew.