For the same reason we have SSL on this site, despite the fact that it has no sex, no storefront, nor any access to my banking or private information.
If everything is SSL secured, then we don't have to explain why any specific thing is SSL secured. The same reason can be applied to use of TOR.
I’m not sure how much more useful that is than just using HN’s automatic ranking for comments, at least outside of parent comments on posts; As far as I can tell, child comments are always ORDER BY score DESC.
Even for top level comments, HN’s algorithm for ranking is pretty useful for assigning “worth”
On posts there's an attempt to suface later comments (with fewer points) so the comment section isn't dominated by earlier posts.
Ordering by score DESC only gives you relative point information, not absolute. Theres additional signal if the top comment has 100 points vs only having 3 (and the bottom post also having 100 vs 1).
"Every site having SSL is a Good Thing because it means you don't need to defend your use of SSL. If more people used Tor it would mean you didn't need to defend your use of Tor."
"Yeah but Y Combinator made a decision that makes it harder for me to auto-generate spam."
The point ranking on comments, which is private, would be of interest to parties training an LLM and want the data annotated, but your point stands.