Yes, I think if a T was overly "sympathetic" before we had even discussed anything, I would not like it. It might be subtly giving the message that you are a poor unfortunate person and even that you are different to the T and they are somehow different and above you.
My T is quite cheerful when we meet and has always framed the therapy work that we are both working as a team to tackle problems. Reading your post makes me realise how important that is.