During the Reconstruction era, what made a white man more qualified to vote than a black man?
I think an argument could be made that, fresh out of slavery where they were denied an education, most freedmen were not qualified to vote.
However, the argument for delayed enfranchisement of blacks had three big problems:
1. This disenfranchisement couldn't fairly be a blanket racial ban because some blacks were educated, plus veterans realistically had to given the vote.
2. Disenfranchising blacks for a lack of education also requires disenfranchising a large number whites who were similarly illiterate and poorly educated.
3. Southerners could not be entrusted to fairly test whites and blacks equally to determine educational eligibility.
Any argument for "ignorant" blacks being used by Republican carpetbagger and scalawag elites also applies to poor whites being similarly used by Redeemers and other Southern conservative elites.