I'm looking to understand how Linux Desktop Environments work with Xserver. I was reading that most window managers don't open sockets directly, instead they use either Xlib bindings for which ever language the WM is being written or you can use higher level bindings XCB; but i would like to know What are the advantages to opening a socket directly to the Xserver?
The question should rather be "What are the advantages of using Xlib instead of a graphical toolkit like gtk"?
Even to master Xlib, you have to spent months or years! It's so intricate that almost every app that has graphical content to display uses a toolkit instead.
Using a plain socket means speaking the X11 protocol directly, which means you would end up recreating Xlib (no, you wouldn't finish!)
As an analogy, plain socket ~ machine code, xlib ~ assembly code, toolkit ~ higher level language. (notwithstanding that xlib does a little maintenance for you, but I guess it's rather neglectable)