Shouldn't String Package concept be inside Strings concept?

I recently started Go track as part of the #12in23 challenge and learning from concepts. I must say it is such a well-designed and structured track. I have just 1 question: why there is a separate “String Package” concept where “Strings” covers that and more.

The Strings concept does not delve into the String package. It explains how the string datatype works. It does mention the package, but only briefly. The String package concept assumes you are familiar with the string datatype and discusses the functions found in that particular package.