Even being pro-Trust, the AoE thing would probably take away the major advantage to running with players; speed.

Which is why I think they devs keep that quirk in place. It's always way faster to do dungeon content with other players. If it's even only a little faster because the NPCs aren't overgeared, I think even more players would opt for it instead of roulettes.

I assume this is probably why some skills the NPC characters can use in solo instances and cutscenes aren't accessible to them in Trusts, either.

Krile's new Butterfly Motif is disgusting strong, for example, and pulling big would probably be way easier if G'raha could use that overpowered Break to stunlock everything while on BLM or PLD or Vanish in general. But Y'shtola still has access to cure on BLM and Urianger has a Death spell, so it's all over the place with gimmicks.

So it has room to grow but it shouldn't grow too much, either.