To actually answer OP's question:
I'd be sad, honestly. I like McD as a human and think he's a rock solid B+ coach, who's been an A- before. I completely acknowledge that there isn't much left in the "what else he can try" bucket. Do not fire him until there is an A-level coaching candidate available, though. I will stand by that. I'll take Year 9 over Tomlin, McDaniels, or Daboll.
The months/weeks in-between McD and his replacement will honestly be pretty terrifying, but I'm sure we will find ourselves supporting whoever gets hired regardless of who it is. Like Tomlin, McDaniels, or Daboll.