Mostly, I just hate the treadmill.
Over the last decade and a half I've written dozens of small tools, applets, etc to hone my desktop environment I use. Half of those have required patching, some don't work at all (like a nifty oneliner I used to kill of hung ssh connections by targeting the ssh process name, that no longer includes the ip or domain).
I will use X11 until I can't - simply because I do not want to rewrite my tooling.