It's not about manipulation, or at least it definitely shouldn't be. It's that in psychoanalytic/psychodynamic therapy, things are often designed to allow transference (of all kinds, not just loving or erotic or positive transference) to develop and be explored unhindered, so that it can be worked with therapeutically if/when it shows up.

With a bad therapist, that could be manipulative. With a good one, it's more about following the client's lead with whatever develops, including transference, and using all of what shows up in therapy as a window into the client's world and a tool for moving therapy forward.