There is a standard <wfw:commentRss> item that exists in almost any Wordpress blog feed. And my feed reader (https://bazqux.com) supports it for years.
But blog post comments is completely another medium from Twitter. It requires you to sign in and, since comment will be there forever, you usually put more effort in it. So comments are more rare and of higher quality. But at the same time you could sign in as anonymous and put your spam link or some ego bullshit -- which frequently happen on popular sites. So it's very dependent from community.
And if you comment on some blog post only readers of this post will see (and they will know the context). When you comment on Twitter -- anybody could see. Together with 280 character limit this leads to completely different kind of discussion.
But blog post comments is completely another medium from Twitter. It requires you to sign in and, since comment will be there forever, you usually put more effort in it. So comments are more rare and of higher quality. But at the same time you could sign in as anonymous and put your spam link or some ego bullshit -- which frequently happen on popular sites. So it's very dependent from community.
And if you comment on some blog post only readers of this post will see (and they will know the context). When you comment on Twitter -- anybody could see. Together with 280 character limit this leads to completely different kind of discussion.