Hypothesis time. We only observe one timeline's Hououin at a time. The question is, does Reading Steiner also rip our mad scientist from other timelines?
I feel like that just one timeline wouldn't justify the amount of feedback he experiences,
That would explain in the 0 VN why one trip could break him so much. Imagine the exponential psychological element of seeing Mayuri die time after time. Then the compounding of Kuristina.