It's a reasonable price because the dlc is 10$ and the 12 months of Nintendo online is 20$.
Nintendo has announced that it will offer a retail version of Tetris 99 in Japan. The game will be available in stores starting this August for 3,148 yen.
All purchases come with access to Tetris 99 as well as the DLC. A 12-month Nintendo Switch Online subscription is also included.