Internet users are a million times too quick to jump to the conclusion that other internet users must be dishonest, shills, or spies, simply because they hold a different view. The explanation is nearly always much more mundane. Meanwhile such accusations are toxic in their own right—they have a poisonous effect on HN. That's why the guidelines rule out making these insinuations. I've posted a lot about this if you or anyone want more explanation:
https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme....
To pick just one possible explanation, sometimes people feel so strongly about a topic that they are propelled into making a new account where they had previously been lurking. I don't know which account you're referring to, so I don't know if that's the case here. However, you don't need to "call" them anything. You can respond if you want to, as long as you do so thoughtfully and substantively and without personal swipes.
https://news.ycombinator.com/newsguidelines.html
Edit: if you mean https://news.ycombinator.com/user?id=kingkong2022, we banned that account for egregiously breaking the site guidelines. A better way to express your frustration would have been to flag the egregious comments (see https://news.ycombinator.com/newsfaq.html). That brings them to moderator attention. You could also have emailed us at hn@ycombinator.com, which would have brought it to our attention sooner.