There's a way to do that on Medium. You're talking about expanding on a topic. In the comments is not a good way as it lands like whataboutism and deflection.

You write your own In Response To article.

In it, you link to the original article and any other Reference Medium article. In your opening, you'd make a statement or two validating or appreciating what you agree with or whatever point particularly drew your attention. Then a statement about why you wanted to expand on that and why you feel it's important. Cause, the niceties, right? And also, you'll want a recap of sorts for people who just came into that particular content to catch up.

Then you launch into your main body and make your argument. Wrap it up with an acknowledging statement of the original work and if needed, an admonishment or reminder that this isn't beating up on the OP or a disagreement, it's just an expansion of thought.

The In Response To Article doesn't have to be a disagreement or a rebuttal.