When you say "home" page.... are you talking about the Forum view (as exampled in the first image)... or do you have an actual landing page using a page node and the Index page route?
Reason I asked is that example only showed on my sites Forum List Main Page, but as shown, did NOT show in any of the categories (as shown in the last image).
I created a new widget for use and did not use any of the built in... are you using by chance a built in widget?
Maybe try [data-template = "forum_list"] in the display condition?