I want no part of Aaron Glenn as a HC

Yes, obviously all coaches should be judged base on one terrible game. Like Dan Quinn. He blew a 28-3 lead in the Super Bowl. He is obviously a terrible HC and nobody should ever give him a HC job again after that game.
Despite his Falcons making a decent post-season run the next year in 2017 and losing a close, very winnable game @ Philly, his tenure in Atlanta following that historic, catastrophic 28-3 second-half SB loss to NE was never the same. It didnt help that Quinn lost a highly-creative, innovative OC in Kyle Shanahan who briefly turned just good Matt Ryan into an NFL MVP for 2016 season, regressed back to being just "really good" QB and his team's roster and depth aged, lot older, and he made some less than intelligent or wise draft picks.

It took Quinn sort of going back to the drawing board, re-learning some of the nuances and lessons of being a great DC and maximizing his second chance. It's also probable that maybe Quinn was a bit too young and inexperienced about 10 years ago going into his first HC job with Falcons. He seems far more seasoned, more prepared as a HC, not as impulsive and while he's very lucky he hit the lottery with a rookie phenom QB, he made sure to maximize the talent base around him and ensure he'd still be successful while he was learning the complexities of an NFL offense.