The Straw Hat Pirates don't have a chronicler on board at present, and none of its members seem to be filling the role. Even if someone who matches the job description eventually ends up joining the crew, there won't be much chronicling to do. As One Piece has already started its final saga, it is safe to assume the Straw Hat Pirates' journey is coming to an end sooner than later. All that could be written at this point is probably how the crew members achieve their individual dreams. Not that those events aren't notable, but most of their adventures will remain undocumented -- and that's where the problem lies.
A major consequence of the Straw Hats not having a chronicler is that their accomplishments and heroic acts may be forgotten or distorted over time. Without a reliable record of their adventures, the crew's legacy will slowly fade in the annals of time. This is particularly problematic given the many large-scale organizations they've offended. Their actions often have profound impacts, and without documentation, those impacts are likely to be accredited to others. The fact that they are pirates also doesn't help their cause.