It's absurd to say that you shouldn't criticize a person's actions unless you first fix the systemic problems in our entire economic system.
Anyway, change very well can come from attacking people. Publically criticizing actions which are harmful is part of the way that we, as a society, build up the standards and norms by which we judge individuals' actions--and, ultimately, form legislation and other institutions to diminish harm and exploitation. The idea of "Don't hate the player, hate the game" is an attack on morality as such.
You can reason with people, sometimes. Attacking them triggers the competitive urge and it becomes about winning rather than the thing you originally intended to do.
The anti-tobacco movement is a prime example of this, just as were the people who brought you Prohibition.
Anyway, change very well can come from attacking people. Publically criticizing actions which are harmful is part of the way that we, as a society, build up the standards and norms by which we judge individuals' actions--and, ultimately, form legislation and other institutions to diminish harm and exploitation. The idea of "Don't hate the player, hate the game" is an attack on morality as such.