I can completely understand wanting to differentiate from Reddit, but to me, this is a matter of convenience and priority. Putting right after the article implies commenting on the article is emphasized. Putting it at the bottom of the comment page implies a want to comment on the comments.
Maybe there’s a reason I’m not seeing here? Am I just dumb?
To be honest, when I was on Reddit, I read all the comments in a post once or twice per month, or when the post was really interesting and with discussion potential (again, very scarcely).
Since I’m here, I read all the comments in a post every time I visit a post, except for four times, I guess. But yes, I can read everything, and I’m also able to know whether it’s being said what I want to say.