Kingdom Come: Deliverance - non-fantasy, medieval open-world, aiming a little bit more at realism, great for history freaks
The Witcher 3 - no explanations needed :) and it's dirty cheap,
Cyberpunk 2077 - it already is a great game and it will be majorly overhauled when expansion comes out, so maybe worth getting it now when it is on sale,
Return of the Obra Dinn - phenomenal, unique, detective experience
Disco Elysium - one of the best writings in games ever, unique RPG systems
All Stalker games are great if you are into classic Euro-jank ;)
@HighStorm89
Lots of great games there. My favorites: