I obviously agree with the OP.
Deceived, Metaphysical Destruction of an individual isn't the only way Existence Erasure can be granted. That is just very common in most cases, so a lot of users assume that to be the case. If you were to read
the page, it never claims that such is needed. In fact, it quite literally indicates that while Metaphysical Destruction can be Existence Erasure, it's not a requirement:
Existence Erasure is the simple power to remove something from existence, leaving nothing behind, a level of destruction beyond incineration, vaporization, and atomization. Powerful enough uses of this ability can even erase the mind and soul, if not more fundamental aspects of one's existence, such as concepts.
The wording in the sentence, specifically the usage of 'powerful enough' implies that being able to preform Metaphysical Destruction is a step above
normal Existence Erasure, which would be regular destruction "
leaving nothing behind, a level of destruction beyond incineration, vaporization, and atomization."
Crabwhale and
Deagonx, the only mention of disintegration came from Brook and a random pirate. 2 individuals whose knowledge comes from what they've seen happen to others. Literally every other source states a version of complete destruction being a result of stepping into the sun after losing your shadow.
From the people being erased themselves, to WoG databooks. On top of that, as KingTempest brought up in the OP, a
part of the individual's body needs to be remained in order to come back from the effects of the Sun. If those without shadows were simply being disintegrated, which according to Crabwhale's dictionary definition is to "break down into smaller parts," they would be able to come back, which we know is not possible.
tl;dr, Deceived is misunderstanding the
requirements for Existence Erasure, and Crabwhale's logic that Deagonx agreed with is inherently flawed due to the nature of the ability itself.