I don’t think any legitimate therapist would claim to be able to cure someone in a limited number of sessions. What they might say is that you may see results in given number and of sessions.
but that’s what they claim.
It’s ridiculous to say that Noone can suffer from just depression or just anxiety. Take a look at the DSM. The criteria for depression is wildly different.
No, it’s ridiculous to say that you’ve ever met someone who has one but not the other.