An account doesn't have to be problematic for you to not want to see their comments. I have several handles in mind where I'd add them to such a list if it were a feature. Nothing against the people in particular, but sometimes when I see a handle (like others said, very often old accounts with high karma), I already know what they will go on about merely just based off the title of the submission and having unintentionally gleaned what topics they usually comment on just by being on HN for a while. It's a waste of time to read those comments, at least for me. Wouldn't hurt them if they lost my attention. I am not bothered by it enough to vibe code a browser extension for it, though. That threshold is a bit higher, I did it for blocking certain domains; there is only so many times I can sit through an article or an "essay" which should have been a podcast.