Would be funny if the interviewer wrote the exact same blog post; "I had the worst candidate interview today, I asked him a simple ice-breaker question before getting into more technical stuff, and he just went off about his family and relationships for an hour; weirdest interview I ever gave."
Yep. This is definitely an OP-is-autistic problem, or is perhaps inexperienced. Not an interviewer problem. Keep it professional. If an interviewer asks a personal question then you simply refuse to answer (politely), or steer it back towards a professional context. If they persist then you end the interview.
I've had that before. I asked a woman to walk me through her career (I told her I've obviously seen the profile before, but I'd love to hear the elevator pitch directly from her) and she started off by saying,"Well, you need to know that I was raised in a cult."
And, yeah, I feel bad for her. But also: time and place.
I passed on her because she didn't have the technical skills, but that was definitely a case of the setting not being right.
“He kept talking about dead babies, failed relationships and the time he cheated in an exam in grade five. Fifteen minutes in and I wondered not whether I would hire him, but if he would kill me and wear my skin if I didn’t. Or did. Little difference.”
you think that's what it was? The people with 100% of the power in this situation did everything 100% correct and you're not victim-blaming at all?
The description of the interview seems like it was explicitly non-technical, though.