Bingo. We all want him gone based on what happened this year and where we sit today. A year ago today, no one with a sane mind could have predicted that Diaco would implode on and off the field the way he did. Exactly as you put, he was kooky but he wasn't endangering players' safety, making psychotic statements to the press which prompt them to write that he's out of touch with reality, and not scoring for nearly 60 straight drives. He had improved by four wins, beat the Peach Bowl champion, and had a veteran and fairly talented squad returning in 2016. He was garnering interest from other schools, including at least one from the P5. To offer him an extension at that point was not at all unheard of or worthy of the vitriol being thrown today.
As freescooter said, starting with the Maine and Navy games, and as the season progressed, the red flags starting increasing exponentially to a point no one could have reasonably imagined. Of course those who had an irrational hatred of him from the start or after his first season will claim they were right, but that's little more than a broken clock being right twice a day. Not a single person with a sound understanding of football, and college football specifically, would have predicted we'd be as bad as we were and that Diaco would catastrophically implode on and off the field as he did.