Having played more than 100 hours, I want to play again and again. The world is huge, you can always stumble upon interesting places or just problems.
A casual player can follow the story or side quests on minimum difficulty. The hardcore player is offered difficulties that can challenge the most skillful player. Several options for Geralt's development increase replayability, and the presence of different options only strengthens the desire to play through the game again and again.
Unlike many other modern games, the developers seriously bothered with the subject of nonlinearity. You can follow the paved path, or you can turn to the side and start the story quest from a completely different place. And you won’t have crooked dialogues that spoil the entire plot up to this point.
I don’t know whether something will soon appear that can surpass the witcher in terms of the totality of impressions. But this game (especially considering the publisher’s extremely lenient pricing policy) simply must be in the collection of a modern gamer.