Agreed on the first part about overachieving and getting a lucky break to make the playoffs, but it was always going to be a two year rebuild considering the cap space. So like it or not, they got rid of everyone they didn't see in a Bills uni in 2019, regardless of how it impacted '17 (turns out very little) or '18 (turns out quite a bit).
And by the way, people drastically underestimate how much the unexpected losses of Wood and Incognito killed this season. If those guys are playing, McCoy is still running, Allen is protected better, and they don't have the worst offense in history. Yes, they'd still suck but it wouldn't be this level of dumpster fire.
You'd have to go back a few decades but I'm sure a fan in Chicago can think of at least one example!