The Ynnari storyline and the introduction of Vashtorr in the Lore changes everything
The two most powerful civilizations during the most destructive war in this Grimdark Universe ALLIED TOGETHER just to fight Chaos 60 Million Years Ago. Neither unrivaled magic nor unrivaled technology alone could beat Chaos when they were much weaker back then
(Gav Thrope might have spoiled how Neoth, Ollianius Pius and the others are going to beat Horus in the HH Finale. Thematically.)
Seriously, where are these Uber Daemons present day!?! Not even the Emperor in his prime could take on a dozen of these Warp-monsters let alone BILLIONS!
Imagine a Daemon capable of fighting an Eldar Psyker a hundred times more powerful than Eldrad and a Necron Phaeron that is slightly below the Silent King in power at the same time!!!
Vashtorr is the only Daemon confirmed to be during or before the WiH. Be'lakor is implied to be from that time due to his rivalry with Vashtorr
Ironically, modern Lore gives certain similarities to the C'tan and Chaos Gods (except the former is infinitely weaker tham the latter). Vashtorr and the Void Dragon both emphasize technology. The Nightbringer is physically affected by emotions. The WiH Daemons don't seem to be negatively affected by emotions and symbols