That's, how this game has been working for ages. That's because Blizzard try to squeeze maximum profit out from such systems before actually nerfing them. And, I guess, this is by design, because they don't learn any lessons.
Examples:
1) WotLK class balance, godlike Paladins and DKs, crappy Shamans, etc. Problem isn't fixed in time.
2) Cata 4.0 heroics were obviously overtuned. Problem isn't fixed in time.
3) All rewards gated behind rep grinds in MOP, while reps are only available from mandatory dailies. Problem isn't fixed in time.
4) WOD flying removal nonsense. Problem isn't fixed in time.
5) Legion grind/RNG/time-gating crap. Problem isn't fixed in time.
6) BFA azerite/essences/cloak/corruptions. Problem isn't fixed in time.
P.S. Garrisons are ok.