Are you asking them to be specific about what they dislike or something?
I feel like the answer to "What practices?" is obvious: "The reason the submissions were being killed is that the GitHub account's address had been banned on HN due to previously being submitted by spam bots."
I was wondering what “moderation practices” related to this story they thought warranted people having a worse opinion of HN moderation? It's unlikely they were referring to automated spam filters.
I feel like the answer to "What practices?" is obvious: "The reason the submissions were being killed is that the GitHub account's address had been banned on HN due to previously being submitted by spam bots."