If you're seeing their other comments, it must be because you have 'showdead' turned on in your profile. Anyone is welcome to turn that on and see all the comments that have been killed for various reasons, but it's important to understand that if you do, you're signing up to see the worst that the internet brings to HN.

As I mentioned at https://news.ycombinator.com/item?id=43538728, users sometimes forget that they turned 'showdead' on, then wonder why they're seeing such dreadful stuff in the comments. Could it be that that's what happened in this case?