I agree about system design, but I think - especially in the context of your networking example - the complexity lives below the OS and not a case where it's a lack of effort.

Networking protocols, connections, error states, etc are inherently complex and require equally sophisticated handling that linux may not always do. Some software chooses not to handle at all and expose directly to the user - but others like KDE simply lack the millions of dev-hours of polish that Windows and Mac have.