That the bishops specify concrete evils is not only legitimate, it is helpful, salutary, and needed. All people, including conservatives and liberals, tend to neglect certain goods. That the bishops point out these neglects and call us to attend to them is also needed, frequently. But specifying for us how we ought to act specifically is not. Specifying concrete political goods, and especially the means to attain them, is almost always an imprudent action on the part of the bishops' institutions in our society.
Nobody is obliged to pursue a particular political good in a particular way at a particular time.
While we are all obliged to help the poor, we may have many different views on the best way to do so. Some will think that one particular way is not helpful and that another is more helpful. It is not the USCC's role to say that we should elect this particular public way of helping. The USCC's quadrennial political responsibility pronouncements are not very prescriptive on the evils in our nation, other than on abortion, but they are repeatedly very prescriptive on the good to be pursued and the means to be used in pursuing them. They do not clearly analyze and teach where in public policy the commandments of God are violated.