I'd strongly argue the character of Art himself has transcended any popularity of the movies themselves and honestly shouldn't be conflated. A bizarre amount of people who have never seen any of the movies and aren't even horror hounds know who Art is and recognize him, and thats frankly all you need. My 60 year old mom knows who Art the Clown is.
Even if it means toning down the actual content of the movies, Art himself is undeniably a strong figure for advertising a horror event.
It's not outside the realm of possibility they just do a semi-original concept using Art and collaborate with the filmmakers, therefore skipping over the controversial aspects of the films while also having the extra marketing boost of being able to say they have something fresh for the fans.