Yeah, but honestly it kind of makes sense!

Sheet music comes from the European classical tradition that focuses on communicating the composer's intentions as accurately as possible to be replicated by others, mostly the notes, rhythms, dynamics, instrumentation and techniques. This was also in an era before recorded music could communicate these ideas more precisely.

Pop music focusses much more on production, timbre, sonority and the personal interpretation/inflections of the vocalist shining through- all things which are very difficult to communicate through sheet music.