Rules of Chess

This is a game from Grand Prix Hamburg 2019 between the eventual winner Alexander Grischuk and David Navara. At move 15, Grischuk playing black has his queen out in the open with no other pieces developed. It seemingly disobeys the golden rule of chess which is to develop your pieces. There is an open file aiming at his king.

To be fair, by move six, he had castled with ample development. It's only after lengthy piece exchange that the above position is revealed.

Here is the full game where you can judge for yourself if Grischuk follows rules of chess.

Does he bring his queen out too early? Is it ok to move his dark squared bishop twice before move 10?

He went on to win the game and the tournament so perhaps rules don't need to apply for grandmasters who research openings with the utmost preparation. Or perhaps he thought his opponent would be much less likely to research such a seemingly weak position. Is this even a valid strategy in chess?