m+ - doesn’t change for months, its stale after a while with a few additions getting gear later on, I don’t think people enjoy running 5-6 mythic for months.
PVP - Never gets changes other then stats, maybe a new map rarely, the ranking system is only for the boosters and 500 people at high rank. New maps would just keep people around in general, we don’t need corny new modes, half the time nobody enjoys them and the rewards aren’t worth playing for the amount of honor or conquest.
Raids - Not a lot of people have time for 4+ hour raids or want to even join a guild to be in them. Even though that used to be the best times with friends on a day off from work.
If you speed up the game things die quickly unless you add more things in it because it gets stale doing the same thing over and over and months go by people don’t care to play as much because they don’t have much to do other than farm gold, get gear that constantly switches with updates even then if the build changes you still are doing the same thing repetitively on the same M+ or same raid or same pvp maps, nobody wants that.
The auction house is a blessing and a curse, its what kills the game later on but you need it, things farmed overtime kills the professions and gear later in game and prices dive down to nothing.
possible solution, releasing new expansions every 6 months would definitely keeps people playing because 4 months most things are under priced or worth nothing from auction and farming overtime becomes useless. if you speed up the game then speed up the expansions. most get bored after 4-6 months other than the pro’s who are a hair compared to player base. so 4th month put that new area out to keep people around and enjoy the time, 2 months later put out an expansion.
hopefully this helps the devs.