I’m purely speculating here based on my own observations, but you have to remember that Dream’s approach seems to trend more towards facilitation. SZ’s approach seems to trend more towards state or end result.
So if Dream were to make a field making me feel like I drank water, he would code the coldness of the glass, the condensation, my bodily reactions to drinking water, its after effects, and then seal it with “don’t let the idiot drink water if it’ll over hydrate them”.
SZ’s approach seems to be more “Here’s water” or the state of having had water.
Not commenting on the effectiveness or anything beyond how the fields feel and seem to act. But if I were SZ and that’s how I knew to do things, I’d be extremely wary of bringing in entities as well, because they do occupy a full spectrum, beneficial or not. It would require, I would imagine, a very subtle approach to guarantee that interaction is positive.