As Will McAvoy says, sometimes it's just one thing. If not for a teen pregnancy maybe we're never introduced to Martin Luther King, Jr., and if not for a wobbly chair maybe we don't survive the Great Depression, and if not for a unseasonably cold night in Cape Canaveral maybe the Challenger doesn't explode over the Atlantic. And if not for a shot clock in basketball game maybe Jerry Dantana gets away with editing the raw footage of General Stomtonovich, and is painted a hero instead of a villainous weasel.
Or maybe not. The one-true-fk-up narrative for how Genoa finally fell apart is a compelling one, but it's also one that's already been debunked throughout the season, including the opener when Will recounts all the small coincidences that led to the report, like Jim heading off to New Hampshire and leaving the door open for Jerry. You can continue to back that train up all the way up to when Maggie accidentally professed her love to Jim while he was riding the tour bus, or you can wonder what would have happened with Genoa if Maggie had never been born at all, or at least picked a different major in college.
Yes, you can always blame the little things when it's convenient or you can celebrate them when they break your way. It's why every questionable call at the end of a football game is seen as the significant one even though it was just one of a hundred cumulative calls. You have to be realistic and look at the whole picture, not just the easy stuff. That's why Will finally realizes that maybe the team just stopped being good at their jobs.
Genoa happened. "It happened." But the MOP suits were for protection, and it was white phosphorus — not sarin — used for spotting the camp, and @Hamni8's cell plan ran out. And Sweeney had a brain injury, and Valenzuela's confirmations we're empty at best, and Charlie's source is, unfortunately, fking insane. Whoops.
Genoa was, in fact, an institutional failure, and to quote another work of Aaron Sorkin, "any attempt to prove otherwise is futile 'cause it just ain't true." Jerry brought it to the table and doctored a major piece of evidence, but everyone is to blame. Maybe Mac most of all. Because nobody trusts Jerry, and it seems like no one really likes him much, either, but Mac's willingness to run the story was all that Will and Jim and Neal and Sloan and the rest of the room needed to get behind it. She's the hinge.
Then New Night's failures with Genoa stop them from breaking Benghazi wide open because they no longer trust their sources and they can't risk being that unfathomably wrong twice in one week. That's not going to do much for Will's crisis of confidence, nor is the fact that he's single again. So he and Charlie and the rest of the ACN News Division plan to resign after the election.
Luckily for them, the usually hate-filled Jane Fonda is stoned and horny for Daniel Craig, as well as rich and pissed. Instead of accepting their resignations for a massive institutional failure, she explains how she'd rather fire them for something petty. She also uses the term "hizzy" wants them to get the trust of the people back. How? No idea. Because it's never just one thing, especially when you accuse the U.S. Military of war crimes punishable by death.