Any chance we can get Trust system as open world content?

[Enkidoh]

I'm not sure how they'd make that work..? I don't think they want 10,000 Thancred's running around :O

Well, the FFXI version gets around that by outright stating that they're not the actual NPCs you're using but simply a magical construct you're summoning to your side (think Carbuncle but with a famous npc), with a preset set of commands and actions to use (and limited robotic dialogue). There was even an official story on the FFXI website that shows a Trust NPC summoned by an 'adventurer' meeting the actual npc it's based on, with the npc not too impressed with her magical dopelganger.

But yeah, as others have said, there is virtually no need for the Trust system open-world here as the Chocobo Companion system already satisfies that.