He's got a ton of talent to work with, though.
The "QB guru" has a fantastic QB that he started Tom Savage over (the "not starting the rookie immediately" thing doesn't excuse him, either, since he started Watson after half a game). He's got one of if not the best WR in the game along with another great one. He's got a real left tackle. He had one of the best defensive ends in football until he, as the de facto GM who is going to remain the GM next year, traded him away for a half-eaten hot dog.
His playcalling and in-game decision making has been questionable his entire tenure - I've read innumerable gripes from Texans fans about the former in particular - and they just keep pooping the bed in the playoffs. Last year's loss to the Colts was just flat out embarrassing. They weren't ready to play against the Bills and survived by virtue of the Bills being the Bills. And then there's today. There's no shame to losing to Patrick Mahomes; there is shame in giving up 7 unanswered touchdowns in under 20 game minutes.