It’s what he’s supposed to do. Special Counsels are there for situations when DOJ investigations & prosecutions fall afoul of politics - the investigation is in the hands of the same prosecutor as before, he just has the Special Prosecutor hat. Most important, he’s a career person, not an appointed political hack.
Now the investigation is under a career prosecutor, with rules & norms that keep politicians at arms’ reach, be they Republican or Democratic, and they can’t do things like yoink budgets or retaliate nearly so easily.