Shadowlands has my vote based purely on the game and how much fun I have. I had more fun in WoD, which would be my second choice because I enjoyed classes more. But it is very close. Both are bad because of endgame issues.
WoD simply did not have a lot to do outside of instanced content. Everybody was in their Garrisons all the time. Too much effort was put in to make the Garrisons the main content.
Shadowlands leaves me with a similar feeling. There is more to do but the content there (world quests mostly) is hugely disappointing. It isn’t as good as old dailies at telling a story and getting me involved with the land. It’s very mechanical. Besides that we are focusing on our covenant which is like our garrison but not as special actually. The systems are too much.
Both expansions result in un motivating me to want to play or even level an alt because getting to max feels like the end of an adventure.
I am not certain that their new design is very successful. The outside powers and attaching abilities to weapons, Garrisons, or covenants… it doesn’t work as good as letting our classes shine on their own. The story telling was best in legion if we are looking at the expansions WoD-shadowlands. I am not interested in armor or binds that gives me passives.
I wish they would stop putting so much effort into things that have not added much flavor to the game.