It seems like a normal empathic response to me. And feeling touched, bonded, or angry, uncomfortable in turn would be equally normal reactions to crying. If a T collapsed in tears, I would question what was going on and would probably find it inhibiting at the very least.

My T teared up a few times. I think he worked pretty hard to keep composure because my experience was of struggling with overwhelming emotions that I feared would engulf and destroy me. So to have him be calm and contained was reassuring for me.

I think in general Ts try to modulate their response to counter the client's presentation. So if a client is detached from their emotions, a T may allow more of their own response to show.