Theoretically, it is difficult to distinguish the complete difference between the two.
First of all, I have tasted both kinds of stews, and I feel that the pressure cooker tastes slightly stronger.
The soup entrance of the waterproof stew is more natural, and the stew material will not be as bad as the pressure cooker.
As for the loss of nutrition, there is not enough evidence to show that there are obvious differences in nutrition between the two soup stews.