Why Captain Holt Became A Petty Person In Brooklyn Nine Nine Season 7?

Brooklyn Nine Nine Season 7 released on Netflix on 10th February'21 and it wasn't as I expected it to be. If you don't know, they demoted Captain Holt to some regular officer. The problem isn't his demotion but how he changed as a human. Captain Holt was competitive, yet poised. He used to be the smartest among them but all of a sudden he became a cranky person. He even kept on cracking jokes about Deputy Commissioner, Wunch's death and refused to accept Julie Kim as his new captain. Here, the makers are trying to show how a human frees himself from his obligations and becomes more vulnerable as he tries to cope up with his failure. Further in the season, as he returns to his position as the Captain of 99, we see him back to his normal self. However, now he has flexible conversations with his employees and is readily accepts change. So does a person's professional stature create different personalities of him?