So this is going to be short. The purpose is to clarify what in my view are the roles of each of the parties in the subject is in governance, so that hopefully people do not get guilt-tripped into anything by those who have turned themselves into the accountability police.
First, citizens. The main role of citizen in a democracy is to participate. Examine the options presented and make an (hopefully) informed choice with your votes. After you do, your role shifts into holding the government OF THE DAY accountable. You can chose to call for dealing with the past governments or draw attention to this, but in all honesty, as a citizen, your main role is to hold the government of the day accountable. So you don’t let anyone shut you down because you supported that government. Or because you supported a past government. Or because you did not criticize the past government in your critique of the current government. The prize you should keep your eye on is keeping the current government on its toes.
Because accountability for past governments usually involves investigation and using the legal framework to exact retribution from those who have abused office, the main responsibility for getting this accountability does not lie on the citizens. Rather, it lies on the government of the day as well as the media to bring past governments to book within the ambits of the law. If they both fail to do this, saying “Nigerians have a short memory” or “XYZ is frustrating our efforts” is not a cop out. The power they possess in the now places this responsibility on them. And pursuing this does not absolve them of delivering proper governance in the now, for which the citizens will hold them accountable for.
Of course this is a simplification, but hopefully, it makes things clear.