Hackernews is not really a platform for building a brand. We have no tools to follow specific people. I don't even care that much if you are the original person I was replaying to or not ;) . We are all random strangers to each other.
But if you have something substantial to say and want to put the effort, then write a blog post, build your own brand and own it.
Yes - they do act like publisher. There is even editorial guide called "guidelines". They will remove things they don't want.
https://news.ycombinator.com/newsguidelines.html
And no - hackernews should not bear the responsibility for whatever we decide to write here, unless it's unlawful.
But I agree on "own your own platform".