"because the argument that Aeon is strong yet unpopular makes no sense."
But weak or strong is a false dichotomy. I would say that overall each of the four factions is roughly equal strength. However, it is more complicated to use the full strength of the Aeon faction compared to say, Thaam and Zthuee spam into Illshavoh spam rallied to wherever the enemy is.
Seraphim having the same play rate as Aeon seems odd to me but idk I don't have the analytics. Also I'm about 900 ladder so maybe that skews it.