He gave up the cert, there was no PFS-only configuration, plus, presumably the FBI got to do their surveillance except instead of the target's email, they could read everyone's. So no, you are not right.
Anyway, I really hope that it leads to adoption of backward-compatible and secure email protocols. Server encryption can't be trusted anymore anyway, we need end-to-end encryption.
Over time, though, it's become increasingly clear Ladar Levison is just a snakeoil salesman who misled his users. He's never acknowledged he did anything wrong. Don't fall for his posturing about 'Freedom'.
https://www.techdirt.com/articles/20131002/17443624734/lavab...
> At approximately 1:30 p.m. CDT on August 2, 2013, Mr. Levison gave the F.B.I. a printout of what he represented to be the encryption keys needed to operate the pen register. This printout, in what appears to be four-point type, consists of eleven pages of largely illegible characters.
And:
> On August 8th, rather than turning over the master key, Levison shut down Lavabit.
That was according to this article from the New Yorker: http://www.newyorker.com/tech/elements/how-lavabit-melted-do...