This is like comparing apples to oranges. Both games do indeed resemble each other or more like genshin does resemble botw to some extent. But they are very different to each other. As for me im having more fun playing genshin than botw. Reasons are because
1. I like the anime style character design.
2. Gacha system for extra fun and that feeling when you pull a 5 star character.
3 Co-op feature for online multiplayer.
4. The lore of the game.
5. The combat system is very fluid and fast paced, Specially the constant switching of characters in mid battle for combos / element combos.
5. And more contents to be added in future updates.