You can say they are just enforcing the law...but that excuse rings hollow.
Consider if a prosecutor only enforces a law against A-type Violators, and never against B-type violators.
What if the A-type Violators are black, and the B-type violators are white? The Dems would not be saying, "They are just enforcing the law." They would be saying this is an abuse of power.
But, since the A-type Violators (allegedly) are "Trumpos," and the B-type violators are mainstream statist Dems, then they are fine with this abuse of power...they would call it "prosecutorial discretion."
I think abuse of power is an abuse of power regardless.