Except it isn't. You cannot compare the FSB to the NKVD.
and is manned by essentially the same people
It isn't. The people who run the NKVD are quite different from the people running the FSB today.
And they were totally different times.
I said KGB. Why do you keep saying NKVD when quoting me talking about the KGB? The NKVD is only relevant in that the KGB was the eventual successor of the NKVD, with a few different name changes and reorganizations in between. Obviously original members of the NKVD would all be dead or very ancient. This is not a problem for people who were members of the KGB who were killing lots of people in recent history.