I’m not aware of any evidence of Assad’s brutality facilitating peace between contentious sects.
Fear is the facilitator. I doubt if you could find a single Syrian Christian who would *not* tell you that the reason the Christians are alive in Syria today is because the Sunnis and Shias are scared shitless of Hafez and Bashar Assad.
Why do you think the fundamentalist muslims from both stripes hate him so much? Because he prevents them from creating a fundamentalist nation where they get to kill the Christians and the Jews.
There’s a video of Assad and his wife on youtube visiting a Christian orphanage run by nuns. From the welcome they gave him, you’d think he was the pope.