I don’t really think it is that confusing - it’s mostly a matter of taking rules very literally, much like we’ve seen in the SotM card game.
For example, Reactive field only triggers upon being attacked (which is not the same as taking damage or even more generally losing health) by a nearby enemy (so not by allies, nor by yourself).
And what it does is: it makes that attacker take damage (like, on their own account - which is not the same as being attacked by you).
Thus, reactive fields cannot cascade. They are not boosted nor hindered, because the owner of the reactive field isn’t doing anything that would apply.
Narratively, I like to think of it as something rather passive: something in your presence/gear/preparation makes the attacker botch it and catch themselves a ricochet, break their fist on your jaw or something like that.