For me (as a man) it’s difficult -yes I’d like to know, no I wouldn’t want to know a partner’s sexual history. And the problem is that once you know you can’t un-know.
Here’s some examples. One partner’s full first sexual experience was as a young teen, when she was raped. The same partner later as a young single adult had an affair with an older, high status, married man and became pregnant. She was white, he was black, living in very white country. She had an abortion.
Another partner, when married and mid-20s, had an affair with a married man. Her comment to me was “I couldn’t help myself, I fell in love”. It ended her marriage. The man’s marriage later ended, not because of the affair with her. He later re-married, and she had another affair with him.
That same partner had a married man who lived overseas and would visit her when travelling on business and stay over. He turned up once when my partner and I were a couple, and she didn’t see him because I was around.
I’m always open about my number of past partners, names and circumstances, but not sexual details. Knowledge can fester. I’m always discreet about what I reveal. Not knowing can’t hurt.