The issue here isn't opinions nor (in this case) the other discourse in the thread. Rather, in this case, it is the account's comments over a long stretch of time.

The question "has an account been using HN primarily for political or ideological battle?" is one of the most important criteria we use in HN moderation. When it is the case, we ask an account to stop and/or end up banning it.

I think if you read the guide that dang linked to, it is clear that the account is breaking the rules for flamebait.

I have read the guide, although i appreciate reaffirming it as the source of truth. What’s hard is from a glance at the posters history their comments don’t seem to break the guidelines, but instead fall into the camp of spirited (albeit strongly so) opinions. Are there specific comments made that weren’t in the spirit of the guidelines? It feels “primarily for ideological purposes” is hard to counter in a discussion because “ideological” itself is a murky term at best.

The point is the pattern (I think the person you are responding to is incorrect about flamebait), you'd go look at the topic of their most recent comments - if the vast majority of interactions are to argue X then that seems to fall under 'idealogical battle'.