Bostrom's definition of a crunch ("The potential of humankind to develop into posthumanity[7] is permanently thwarted although human life continues in some form") isn't coextensive with ChristianKI's "90% of the human population dying by 2100", and dysgenics seems far less likely to cause the latter than the former.

I agree. I guess that ChristianKl guessed that by “the list of existential risks” baiter meant the one in the survey, but I was charitable to baiter and assumed he meant it in a more abstract sense.