Sentis Categories / Tags Confusion

I’m confused about the different AI categories. I’ve posted in the Sentis (category?) since it’s been in public beta: Sentis - Unity Discussions
New posts have been kind of slow there lately. Today I’ve realized that there is another Sentis (tag?) that I can access through this link: Topics tagged sentis
or this list: Unity Discussions

The list / tag-filtered thing has posts that are not visible in the sentis category. And vice versa posts in the Sentis category do not appear in that list or when filtering via the sentis tag. They DO appear in AI Experimental (product area?) though.

The distinction between tags, categories, lists, topics, product areas is super confusing and unclear to me.