I agree it would not be the consumer's fault or responsibility, but in terms of deciding on the overall probability of risk in a profile, some residential ISPs

I agree it would not be the consumer's fault or responsibility, but in terms of deciding on the overall probability of risk in a profile, some residential ISPs do have proportionately more bad traffic than others. We don't attribute a high number of points to this because it doesn't deserve a high weighting but it's probably right to factor it into the score. Having said that it's early days for us and we're still tweaking/testing.