You need to ask yourself "what IS Ryzom?" Surely, it can't be only the code and artwork, right? Isn't its virtual world part of it? Or perhaps isn't it the most important part of it even? So please tell me, how is Ryzom open source now? I can't even GET Ryzom!
What they did is provide an open source engine for you to implement your own MMORPG. Props to them for that. But there are enough other such engines out there, this is nothing special. But they did not open source Ryzom itself. And they shouldn't claim that they did.