That’s what we are looking at. Reno didn’t make an obstruction call on Clinton, Richardson didn’t on Nixon. Barr is acting out of precedent.In an impeachment proceeding, yes. If Articles of Impeachment were brought it would be up to the House to indict the President and then he would be judged by the Senate.
Here, an obstruction of justice indictment would be for an actual criminal proceeding. Seeking an indictment and charging someone with obstruction of justice is done by DOJ prosecutors.