9.0.5 is exactly that, a prepatch. 9.1 chains is probably another 2-3 months away. I wouldnt say its not meaningful dev time, but changes that people have been asking for since launch. Of course most people are/were expecting 9.1 to be here already, regardless of why its not the changes are appreciated. There is no where near as many people online as it was just a few weeks ago, so I feel like even the casuals have completed the story line and people are just unsubbing. Just like people do with other MMO's where they only sub for content updates periodically.
It just may be that I've become apathetic to MMO's, but there is really no point to grind gear anymore. If I think back to playing something when I was little, like Dragon Warrior/Quest - I had to grind levels and gear to see everything. Now, you complete the story, see every dungeon, complete the raid on lfr and you've effectively seen the majority of content the game has to offer. No one has any idea what gear you're wearing because of cosmetics so that appeal is gone as well. I just dont see the point in staying subbed in order to hit leaderboards that benefit me in no way whatsoever. I enjoy playing WoW, but its fast approaching a 20 year old game.. so the appeal of just playing it to be playing it is pretty much gone.