Where's the aether? (Spoilers)

[Lady_Silvermoon]

The people on the Source aren't more powerful than the people from shards for the same reason that 75% of the Ancient population is now in the aetherial sea to be reborn with their full, complete 14/14 souls and it will make little to no difference. I believe YoshiP described it as "maybe they'll be a little cooler, have a bigger mana pool." Their species has been eradicated. Their big thick souls will be stuffed into catboy and bunnygirl bodies, so it won't matter.

[Galvuu]

The people on the Source aren't more powerful than the people from shards for the same reason that 75% of the Ancient population is now in the aetherial sea to be reborn with their full, complete 14/14 souls and it will make little to no difference. I believe YoshiP described it as "maybe they'll be a little cooler, have a bigger mana pool." Their species has been eradicated. Their big thick souls will be stuffed into catboy and bunnygirl bodies, so it won't matter.

Actually, Emet-Selch states outright in Shadowbringers that (part) of the reason why the WoL "towers above their peers" (in terms of might, in context) was because he was "seven times rejoined".
Ofc we also know the last Azem was very powerful and aetherically dense (I recall Venat using the figure "twice as powerful" as her)- putting both together, Emet seems to be have been stating "you've been rejoined seven times" as "your soul is denser/has more aether" to a being which had a dense soul to begin with.