There's the obvious security/privacy point, but I think on a technical basis it would also be useful: the internet is full of pesky middleboxes which meddle wit

There's the obvious security/privacy point, but I think on a technical basis it would also be useful: the internet is full of pesky middleboxes which meddle with content, and this breaks things. For example, sometimes WebSockets can't connect unless run securely because somewhere a middlebox is looking at the content and changing it, expecting it to be HTTP traffic when really it's a websocket. Encryption removes the possibility for infrastructure-breaking middleboxes.