A lot of this is nothing more than Weissmann and pals collecting political intelligence on the opposition party.
Having for example the entire database of the Trump campaign communications and the transition communications is invaluable for Democrats trying to piece together the networks of political operatives, donors and volunteers that pulled off the Trump victory over the Democrats.
With Stone the famed political dirty trickster, they can go back through his communications and see what tricks were pulled on the Democrats and by whom.
This is about payback and using the tools of the criminal justice system to gain political intelligence useful for attacking and counter-attacking Trump and Republicans in the 2020 election.
Maybe Trump and Stone prepared for that event.
Gave the FBI a bunch of garbage?
Hope so.
And to use the Democrat Department of Jesters, the Democrat IRS and the Democrat FBI to target those people before the next election.