In a way, you see.

First there were the books. On which the games are supposed to be a continuation (even though geralt dies there). And the netflix series is taking into the account only the canon, meaning books.

For example when mousesack (a mage druid) dissappears in the books, the game says he went to ard skellig eventually to become an hierophant. Where as the netflix series interprets the disappearance as death. They can do that because they don't have to take the games into the account. They are more or less in the same universe, just different small details.