Interesting paper; had not known of this earlier. Thanks for posting.
Mathematics is the study of Abstractions and Modeling using these abstractions. Entities/Attributes/Rules establishing Relationships (numerical and otherwise) all fall out of this.
The best way to understand this is through the idea of a Formal System - https://en.wikipedia.org/wiki/Formal_system All that the common man thinks of as "Mathematics" are formal systems.
A good example is this wired article How Do People Actually Catch Baseballs? - https://www.wired.com/story/how-do-people-actually-catch-bas... (archive link https://archive.is/Aarww)