The issue of indirect persuasion can be viewed as an issue about manipulation.
Here is how Robert Noggle introduces the topic and hints at the problems of considering indirect persuasion, that is "neither coercion nor rational persuasion", as manipulation or not.
Manipulation is often characterized as a form of influence that is neither coercion nor rational persuasion. But this characterization immediately raises the question: Is every form of influence that is neither coercion nor rational persuasion a form of manipulation? If manipulation does not occupy the entire logical space of influences that are neither rational persuasion nor coercion, then what distinguishes it from other forms of influence that are neither coercion nor rational persuasion?
Here are the other questions:
Is it ironic? Socratic? What does it say about the persons involved?
What it might say about us is that we are not, nor are we able to be, completely rational where direct persuasion can or even should be expected to be effective.
Noggle, Robert, "The Ethics of Manipulation", The Stanford Encyclopedia of Philosophy (Summer 2018 Edition), Edward N. Zalta (ed.), URL = https://plato.stanford.edu/archives/sum2018/entries/ethics-manipulation/.