At first I thought it was amusing that this announcement wasn’t in nested-reply format; then realized you weren’t ready to reformat the whole News and Events > Announcements category.
Here’s some resources I collected when new to Discourse and understanding the flat model: Jeff’s canonical take:
A nicely-done outside note:
Why Discourse uses “Topics” rather than “Threads” (from 2017, before `nested-replies’ was invented.
Lastly, while I may implement nested-replies, I will sorely miss infinite scrolling. I have a nice mouse with a handy free-spinning scroll wheel, but nothing beats grabbing the infinite scroll bar slider and quickly moving through a topic.