People will get upset, but you're ultimately right... Zelda's primary appeal is ludo-centric - the act of playing it is amazing. Everything is based on gameplay systems, and all of those systems are great, from combat to cooking. On the other hand, the story is nothing special at all, and you could say the execution is poor by other AAA studio standards. Of course, here it serves its purpose just fine (and is a big improvement from past Zeldas), but it's not the appeal.
In all of those other games the narrative is a big part of what keeps you playing, and the gameplay systems are nowhere near as complex or varied (or fun) as Zelda's, and typically serve to just keep you ticking over through the story the developer wants to tell. If you stripped away the narrative and had nothing left but the gameplay it might get old quite quickly.
It's a question of how ludo-centric a game is, really. Zelda feels totally different to those other games. I commonly thought of Super Mario games while playing BotW. Because the world isn't really a real place to explore like it is in other games (IQ too weak, textures too blurry etc) but controlling Link in this world is the appeal, like in a Mario game.