They should. And there is something you can do to make it happen. Write your district attorney and encourage others to do that as well. That is how they pick what to work on.
No, that's not how the DOJ picks what to work on. They did not work on indictments of James Comey and Letitia James because someone wrote district attorneys.
Well yes, except the current admin will never prod DOJ on this issue. If people write them letters, there is nonzero chance something will start happening.