There is another benefit in knowing the yichus. The Chasan Sofer explains the gemora in Berochos where Rav Akiva was not selected as the nasi because לית ליה זכות אבות he doesn’t have the zachus from his yichus. So what? It brings to haughtiness, גאווה. He thinks that he is being helped because of his own zachus. Teaching us the need for yichus not that c’v Rav Akiva would use that for his elevation but it should not give that impression. Also, when needed, he can pray to be helped in their zachus.
