If you do the Quel'delar quest chain you get to see the isle of quel'danas restored which was pretty nice. I would love to see an updated silver moon since my main is a blood elf paladin. However the trouble blizzard faces is how new blood elves can be introduced in the new questing zone. inhinestly hate blizzards way of just ditching a place after the expansion it was in is over. This is an MMO. It should be an ever changing world. However this game engine is too old to be able to do that and it would require a lot of work to change dialogues and quests every expansion to reflect the "new world".
TLDR: this is what happens when a game is 12 years old with multiple expansions without changing the core game. Since WoW stays the same game butnisnjust added to they can't make huge changes like normal games can. Other games can just start fresh with a brand new game.