My overwhelming feeling was that he had a few key games coming up (after Ohio State) that would be more-or-less the measuring stick for this season, and maybe for his future. Yesterday was the first one, and they obviously failed miserably.
The team has been built for a long time now, and rightfully so IMO, on front 7 strength defensively, and the O-line being the engine that runs the offense. It's been a long time since they've looked as overmatched in those areas as yesterday, and that includes OSU. I'm surprised but I'll roll with McIntosh if he thinks this is the time, especially when I think of who he most certainly consulted with before making the decision. Don't know how accurate this is but I've heard rumblings that he wasn't happy at all with the changes in CFB recently, if that's the case it may have affected his day-to-day work ethic & enthusiasm (I also wouldn't blame him, but that's another topic). So if that's the case, yeah, it's time.
I would however reject the criticism of his personality, the lifelessness in front of the mic, lack of "fire", etc. He has the same personality as when they've had successful teams. It makes it frustrating to listen to him after a loss, which I get.
At the end of the day, his record here was solid but not over-the-top successful and IIRC his record as the HC at Pitt was maybe a little over .500. Maybe he's one of these guys who was better suited for a coordinator spot as opposed to running the whole show, but takes a HC job because, you know, it's what you're supposed to do when you have the chance. I'm sure that, as far as being the center of attention is concerned, he'd much prefer being surrounded by friends at the bar telling stories than surrounded by mics, cameras, and notepads.
I wish him all the best.