That’s not true. Correspondence therapy is a thing. Plenty of research exists in the area of delivering therapy and the effectiveness of different kinds.
Going into a discussion with "that's not true" might not be the best opener ;)
It's not only my personal experience but even people like Irvine Yalom (in Becoming Myself) note that the special form of therapy is not as relevant as the personal connection.
From a quick glance, correspondence therapy is also used on top of an existing relationship most of the time. So I don't see any problem with my initial hypothesis.
