Everyone here was a cultivator so they obviously knew how to cultivate, some even approaching the Nascent Soul Realm.
They knew that it was a standard for someone to start cultivating one of the six elements with a cultivation method. Some switch to one of the other elements, for one reason or another, but the consensus was that only one element should be cultivated.
Anyone would tell you it was better to focus on one and deepen your understanding of that element on your path to the Nascent Soul Realm. Here, you’d be able to start comprehending and using the laws of that element, as well as the others.
After reaching a sufficient level in all six you’d be able to transform your Nascent Soul into a Divine Soul and enter the legendary Soul Transformation Realm. Wielding the natural laws of heaven and earth in this realm would be nothing but a thought, you’d be considered a god to lower-level cultivators essentially.