For me it depends how much and what kind. My first T almost never shared anything about himself in session but he puts a *** load of very personal stuff on the public internet that I could read and it very much contributed to my losing respect for him - it gives away very effectively how messed up and unaware he is, low standards etc. I see some people loving it though and saying how authentic.

Second T shared many things about himself in sessions when they related to something I had to say. I liked it initially but then it felt like that was all he was doing as a T, we just had good conversations and got to know each-other, but not much else. I now think that it was also quite lazy of him - too easy to just respond with sharing a relatable thing rather than actually getting into my stuff more deeply and providing something useful. Sometimes it felt like he did the disclosures as an avoidance of working harder as a T. The nature of the disclosures were usually good though as they were typically focused on solutions, not mere descriptions of difficulties. I definitely would not like a T who shares a lot about their suffering, traumas, etc as I don't usually like to relate to people very much via negative things and ongoing struggle. But I do like when someone shared effective solutions and how they have overcome hardship.