The purpose of the process is to allow comments to be received. These comments may or may not be used to amend the report, that is up to the reporting body. It helps prevent misunderstandings or minor factual inaccuracies from making it into the final report.
The comments stem from the timescales... 4-5 months to engage with parties that have likely already been involved in the process that generated the draft..
I doubt in this case minor factual inaccuracies will make a hill of beans difference to the reasons for the crash or the people who have been most affected by the events, do you??