Auto-translated
I haven't played SC2, but I've gathered some information about Conflux.
Firstly, you need your own Ubisoft account. Then, this system reminds me of Steam – you can access the internet at any time, view news/updates, and see in-game achievements. Additionally, you can create what's called a "hero dynasty." This part is a bit more complex, but it seems you can create heroes for each faction like building with LEGOs – choose a portrait, bonus, and name. You can then use this "template" in multiplayer. In the campaign, having your own dynasty allows you to choose a bonus before a mission (+gold, +resources, or +artifact).
The video probably presents a trailer that explains why the "old universe isn't dead" :).