zlacker

It isn't frowned upon at all! Substantive comments are best, whether agreeing or disagreeing. But among unsubstantive comments, it's the negative ones that we frown upon, not the positive ones. Here's what pg wrote years ago:

Empty comments can be ok if they're positive. There's nothing wrong with submitting a comment saying just "Thanks." What we especially discourage are comments that are empty and negative—comments that are mere name-calling.

https://news.ycombinator.com/newswelcome.html

>>dang+(OP)
Thanks for taking the time to respond and clear that up for me.

I joined HN fairly late (just a few years ago) and my subjective experience of the rules (as they are lived) is that a 'thanks' comment is almost invariably countered with a snarky 'that is what the upvote button is for' response.

For what it's worth, the vast majority of my experiences here on HN have been positive, and I greatly appreciate how often someone with significant domain knowledge turns up and replies to me in a way that seriously challenges beliefs which I had previously taken to be fact.