Swartz had excellent counsel, federal criminal defense attorneys understand the sentencing guidelines the way we understand singly-linked lists.
I agree, strongly, that there is a massive power disparity between ordinary defendants and prosecutors. But I'm going to gingerly venture that you can't gauge the magnitude of that disparity by the number of cases that plead out. Some component of that is power imbalance, but the greater component of it is that law enforcement generally prosecutes lay-up cases. Many years of reading and listening to Ken White, who is no friend of the DOJ, leads me to believe this is even more true with federal prosecutions.
See https://www.texastribune.org/2017/03/07/report/ for how there is only one county in the country that actually double checks drug tests after someone has plead guilty. The result is that the one county alone manages to exonerate more people each year than the next three states combined.
There is no reason that I know of to believe that Harris County has an abnormal number of people wrongfully convicted. They are only unusual in figuring that out and turning them free later.
Still, the fact that prosecutors seek to create this confusion in the general public makes it likely that they seek to create it in defendant. And stressed out people who should know better often wind up with bad conclusions because stressed out people under pressure don't think well.
That said, Swartz's attorney told Swarts that they would be seeking 7 years. Your lay reading may say that they wouldn't get it. But the gap between what you hear from different sources is extreme. And once you're in front of a judge, I don't trust courts to do the right thing.