Whether if the Monsters house series ends when Epic Universe opens or after, It’s still an annual trend for HHN cause It gets us excited about all the different characters before It opens with the Monsters themed area. Generally, It‘s the easiest IP Orlando could get and do whatever the hell they want cause they can change the formula when they bring them in, and even change the genres if they need to, depending which one is featured.
UM 2019, Bride, and Legends were their own thing separately, but part of the brand. Are they gonna get bored with them anytime soon? Probably not. The Monsters merch also sells too, which is another reason to continue. They are to Universal is what the princesses are to Disney.