When two quantities are directly proportional, a "constant oof proportionality" is required to form an equality. It is true that according to Ohm's Law, the current thru a conductor is directly proportional to the PD across. The constant of proportionality in this case would be (R), the resistance of the conductor in ohms (symbol: Greek letter Omega). Only when R = 1 ohm would the current thru the conductor be 2 A. For all other values of R, the current would be (V / R).
