If you are coming to a blog post of mine that has been shared to you, my assumption is that you want to read my article, and not to be distracted by whatever performance is happening in the comment section. I am aiding you by not even putting a comment section there.
I realize there is a slim chance for there to be enlightening conversation in a blog comment section - but that is not what my blog is for. You are better served doing that here on HN or a more dedicated forum. Here it can be be more visible for others, for people who want to read discourse.
Sending an e-mail is not the same thing, it's like Youtube removing the unlike button count and instead sending the info only to the creator.
This doesn't apply to your blog, but I've seen low quality or misleading content without a possibility to comment. Even worse: scams that include a fake comment section.