The Trust System was prefect, why do we need to level them now?

[SnowVix]

I haven't looked at the trust system until very recently after playing through 5.3 msq only to learn that we now need to level up the trust to level 80 by doing each dungeon 3 times.

This was explained to us that it would need to be done on Shadowbringers launch, and is not new at all. Recently they added the ability to do dungeons in "Scenario mode" which removed the leveling requirement, but also limits you to which trust NPCs were available for that dungeon in the story.