The first Mishna in Brochos states:
מעשה ובאו בניו מבית המשתה אמרו לו לא קרינו את שמע אמר להם אם לא עלה עמוד השחר חייבין אתם לקרות
There was an incident where Rabban Gamliel’s sons returned very late from a wedding hall. They said to him, as they had been preoccupied with celebrating with the groom and bride: We did not recite Shema. He said to them: If the dawn has not yet arrived, you are obligated to recite Shema.
This looks weird to me that a minor incident made its way to the Mishnah - the Oral Law - straight without any discussion, arguments or review.
What is so exceptional, smart, necessary/obligatory in Rabbi's decision to write the story whole in the Mishnah for generations: R"G's sons, coming late, from a party, instead of just stating the conclusion (following) - "wherever the Sages say until midnight, the Mitzvah may be performed until dawn."? Would the Mishnah really be lacking any clarity or information had this story not be included?