I see your point, but I think it's still important to give an end-to-end description, allowing people to tie it all together. The wall of text, if you'd read it

I see your point, but I think it's still important to give an end-to-end description, allowing people to tie it all together. The wall of text, if you'd read it, uses progressive layers in several places (like core Internet routing), specifically to try and avoid information overload for the reader. If a reader were to actually use networks for something (like try to write a program that uses TCP), they would obviously need much more detailed knowledge. At that point, diagrams become necessary, as do much deeper explanations, but the goal of this post was to give an overview of what things are needed to provide end-to-end communication, and why.