I actually think this might hold. The US and Europe already know they can't compete in Syria. If they keep holding on, it just means more pain for the civilians. US and Europe can't just keep arming and training the moderate rebels, to face the Hezbola, Iranian, and Russian military. They just won't hold up. Then you have the group that looks like they can hold Syria, and a member nation says they are terrorists, along with that group seems to have an "understanding" with Syria and Russia. As seen by the Kurdish embassy newly open in Moscow.
I also noticed in the ceasefire, that there is no mention of ousting Asaad. IMO, this is mainly Europe saying they can't handle the refugees, and they need the war to end. And the only way for that to happen is stop the losing battle, and really go after who they need to go after, ISIS and like organizations.