In earlier iterations of WoW casual gearing was a lot more player friendly. Do whatever content you want, get badges/points and buy the second best gear in the game over the course of a few months.
This lowered ingame toxicity by a lot because now casuals weren't forced into high end content for their gear, they could do LFD, LFR and daily quests so friction between casuals and high end players were a lot lower.
However now we have the WoW Token. Casuals with limited time can buy a token and then buy a boost from one of the boosting communities and get their gear that way.
So if Blizzard were to reintroduce the player friendly badge/valor system casuals wouldn't need to buy boosts as much which in turn would hurt the WoW Token sales. A lot of casual players started quitting about a year ago when they realized that they were second class citizens and didn't have any meaningful to look forward to gear wise but I could imagine that a lot of the remaining casuals bought boosts through the WoW Token so that the revenue for WoW stayed roughly the same.