Extroverted feeling ought not be confused with the persona. Although in Jung both refer to the process of adaptation, extroverted feeling is a function of personality. It is a manner of performing and can be an expression of an individual style. By means of it a person gives values and adapts to values in ways that can be highly differentiated, uncollective and original. The persona, on the other hand, is a fundamental archetype of the psyche referring to the manner in which consciousness reflects with society. The persona in Jung's stricter usage of the term, therefore, does not refer to something individual. A developed persona would mean a developed reflection of the collective consensus. If one is a prisoner, or an addict, or a hermit, or a general, one can have a developed persona by behaving in the styles and forms collectively belonging to these patterns of existence. They are archetypal patterns. Feeling may have little or nothing to do with this adaptation, for one can be connected very well to the collective through thinking, intuition, and sensation. In a nutshell: classically, the persona is a collective way of playing a role in the world; the feeling function is an individual instrument of self-affirmation.
— James Hillman Marie-Louise von Franz
The distinction Hillman draws here cuts against a confusion that runs surprisingly deep — the assumption that warmth, sociability, attunement to the room is already feeling in the psychological sense. It is not. A person can be exquisitely calibrated to the collective register, fluent in its emotional codes, impeccably responsive to every social temperature shift, and be operating entirely through thinking or sensation, with feeling barely touched. The persona succeeds precisely when it renders the individual invisible inside the pattern — prisoner, general, therapist, mystic. These are not failures of character. They are functional adaptations, and the most developed among them are the most archetypal, the most thoroughly collective.
What Hillman means by feeling as "an individual instrument of self-affirmation" is something closer to a valuing that can run against the room. It differentiates rather than reflects. It produces an individual style, which means it can be wrong by collective standards and remain itself anyway. This is why inferior feeling is so often invisible to its bearer — not because feeling is absent, but because the persona has been so successfully developed that the individual valuing function has had no occasion to declare itself separate from the roles the world has offered. The question feeling eventually forces is not "what does the group value" but "what do I."
James Hillman Marie-Louise von Franz·Lectures on Jung's Typology·2013