I find the general point interesting, but want to nitpick:

> "items in the deleted state must have a deleted time"

I much prefer making it impossible to represent bad state, like rephrasing at as "items are deleted if their deleted_time property is set". In this case, that makes the deletion atomic: there's never an instant where it's ambiguous if the object was deleted.

That doesn't disagree with his premise. It's an additional recommendation.