Well, he's wrong about this. Quoting the maximum statutory penalty is the standard in news releases, but tells you exactly zero about the negotiations in attorney conferences. US attorneys don't write the press releases, those are done by the most junior lawyers and quote the statutory maximum because it's factual without giving anything away about the government's courtroom strategy.
What if there was no mention of the penalty they were seeking in negotiations or it was left highly ambiguous? In that situation I could see a public press release announcing that you might face 35 years in prison as quite threatening.
The only things that matter to these maximalist dickholes is:
* successful conviction * maximum penalty they can achieve with what they have * if you don't take the plea bargain, make you regret it
If they really hate you, they put people on 'document generation duty', which is cheaper than document review, and throw hundreds of thousands of documents at you during trial. They find the most expensive venue for you, and if you have an employer that has somehow stuck by you this long, they coerce it into letting you go.
The entire goal of this sort of thing is to deprive people of a chance to actually go to trial and stand a chance of acquittal, particularly when gaining a conviction 'honestly' is going to be difficult or expensive.