But how can I evaluate it if I don't play it?

There are beta and demo versions available. Usually, this is enough to get a basic idea of the game.
You can also read reviews. Of course, you might say that your opinion may differ from the opinions of those who wrote the reviews, but that's not entirely true. You can judge the nature of the review and determine how much your preferences overlap with the preferences of that person. In addition, your friends, whose tastes are similar to yours, may give you recommendations.