If it’s really 6M, let’s napkin math it out.
You’d get 500g per world quest, rounded down,around 8 WQs per half-week at first, then 12-13 WQs by the end.
Let’s round it to 10 WQs, so it’s 10k gold (20WQs vs. 500g) per week per char.
6M/ 10k = 600 week-chars of DR quests.
Distribute this value between weeks and chars.
12 chars * 50 weeks, for instance.
This is clearly rounded down (the gold and WQ #), so it was definitely a few less weeks, around 10-15%.