That section was written for people who know little to nothing about Unicode and the ways Unicode can be encoded to bytes. So it starts with the obvious approach -- just spit out a sequence of bytes whose integer values are the code points, which is near enough as makes no difference to how UTF-32 works -- then introduces variable-width encoding through the history of UCS-2 and UTF-16, then gets to UTF-8 and what motivated it.

The advantages/disadvantages of the various encodings is something that could eat up several pieces just as long as the entire post, and for fun I'd probably throw in weird stuff like the attempt to do EBCDIC-compatible UTF instead of ASCII-compatible, etc.