I don't know if there's a way to pardon part of a crime, or reduce a sentence? Hunter clearly did something illegal and should pay for that, but the punishment he got was way above what a normal citizen would have gotten for that crime, especially since he got a plea deal that was just cancelled for for political reason (crazy how quick justice moved in that case but slow walk the fuck out of attempting to overthrow an elected government).
By my understanding, the plea deal was tossed by the judge because it was for the gun charges but also said he wouldn't be charged for unrelated tax crimes, without even pleading guilty to either. That doesn't particularly sound like political persecution to me.