Until now, we had comments under each new video or Member blog post, and Forums as a separate entity, in a secluded cul-de-sac of the site. That just changed.
As of today (11/17/19), when you comment under a video, or a blog post, it’s a Forum topic reply as well. You can still see the most recent comments under the Connect button above. Each new post is a topic on our Forum. From the Forum Comments page, the Last Post column shows you how recently someone replied to that thread.

We Changed. You Don’t Have To.
Although we’ve changed how the comments and forums work, you can still comment on your favorite posts, reply to others’ comments, and delete your own if needed, as you used to do. You can also up-vote the comments you like.
We expect that our Members will have suggestions for improving this, so please us know right here.