Native speakers certainly use spaced repetition, as they hear the same sounds over and over again until they learn them. All an SRS is, is a piece of software that optimizes this process.
Spaced repetition is a scientific phenomenon that has nothing inherently to do with a piece of software. It’s a description of how the brain works and is based on the spacing effect.
SRS is an application of this effect in software form, hence the name, Spaced Repetition Software. So yes, no one uses a term meaning software to describe reading a book.
