More that you can go deeper in context / detail, with images, styling, better links

Rich-embeds in social media/communications platforms, mostly. Simply taking up more space in a Discord/Slack/Teams/$SOCIAL channel with a bold title, an excerpt, and an image adds visibility, context and is more interesting to the viewer.

A link to an HN thread is opaque, uninteresting, and context-less.

Name a blog post that has stuck with you because you learned something useful. Could you search for it and find it easily? Now do the same for an HN comment.

I'm pretty confident I could find any HN post that I remember with the search box at the bottom, or by googling it with site:news.ycombinator.com.

With, half of the blogs that I liked I can't remember the name of the blog, it's probably either been dropped from search engine indexes for being older than a year or two or pushed to the 10th page by better SEO, or the site has simply vanished.

OK, I have little doubt that many readers of HN could find something here, but I think that for the vast majority of people finding a blog post will be a lot easier than an HN post. Styling will be an obvious advantage, you will be able to take a very quick look at a blog post and be able to remember if it's what approximately you saw before or not. You will need to read at least partially through an HN post to gather if it is the wrong one and reject it.

That’s usually easy using Algolia when you have sufficiently unique search terms, but otherwise that’s what I meant by SEO. Any other reasons?