Like Killerdog said, we separate it into damage passive and non-damage passive.
But you have a point. The text is not 100% accurate.
When we first created a passive that deals damage (Explosion Revenge), Staticsphere turned out to be very disgusting during testing. So we made the change on purpose to counter it.
Now that meta has shifted to more “defensive”, we believe instead of changing the Stealth text, we can change how it works.
Therefore, Staticsphere, Bulbieboom and Flocculasaurus’s passive skills will deal damage to the monsters in Stealth or Camouflage. This will be applied in the next update (please don’t ask when is the next update 
).
Thanks