Spiritual consciousness was the most important part of a person.
It could be said that when the physical body died, the soul would remain, and under normal circumstances, it could go to the Netherworld and live for hundreds of years.
If one worked hard in the Netherworld and enhanced their soul's power, they might be rewarded by the Nether God with a chance to reincarnate.
But if the soul was gone, it would truly be the end.
Another reason was that the human soul was very fragile, and if one didn't specialize in spiritual abilities and casually allowed outsiders to enter their soul, it would be easy for outsiders to damage the soul.
It was like a small child breaking into a glass room.
A casual move could damage the soul.
Besides, there would be a lot of private things in the spiritual consciousness, good and bad, and many secrets.