Demon Slayer: Kimetsu no Yaiba" is often considered one of the top anime series of 23 in my opinion. The series gained significant popularity due to its engaging storytelling, stunning animation, and intense action sequences. The series follows the journey of Tanjiro Kamado as he fights demon and seeks a cure for his sister, who has turned into a demon.
Please note that opinions on the top anime of a given year may vary among individuals, and there are several other notable anime series from this year that are worth mentioning, such as "Jujutsu Kaisen", "The Promised Neverland Season 2", "Haikyuu!! For The Top ", and "Attack on Titan Season 4". It is always recommended to explore different genres and watch several series to find what appeals to your personal preference.