Decay and other active items proc Escalating Exposure but do not proc Mystic Slow

[weebstrangler]

Decay's damage over time is spirit damage. It correctly causes Escalating Exposure stacks to accumulate, which triggers from "dealing spirit damage". Why does it not apply Suppressor or Mystic Slow? These items state they trigger "when you deal spirit damage". All active spirit damage items cause Escalating Exposure to trigger, but none of them trigger Suppressor and Mystic Slow. If this is an intended distinction, there should be some verbiage to denote the case of Escalating working and the others not.