I think Spider-Man. No idea why people love that so much. Sure, it's cool to be him and swing a little bit around the city but in the end it's still not really a great open-world game in my opinion. If it would be popular for some multiplayer mode which people often love to play together I could maybe understand it but just for the singleplayer I really wonder why it's so beloved. The world is just mehh and drags the good story down.
Edit: to be fair it doesn't have a super high metascore but many gamers seem to put that game above everything.







