The category \(\mathrm{Pr}^\mathrm{L}\) of presentable \(\infty\)-categories is a place where one can do surprising amounts of "algebra", and the study of presentable categories with extra structure often helps in the study of objects within those presentable categories. This higher algebra has become more and more studied in recent times under the impetus of Efimov and his continuous K-theory, as well as Scholze and Stefanich's Gestalten, which uses this higher categorical algebra as the basic foundation of a new type of geometry.
Personally, categorification is also one of my favourite tricks in math.