If women should be banned from voting because they’re more likely to vote lib then perhaps men should be banned from driving because they’re more likely to speed and drive drunk. Or we could embrace the “individualism” part of conservatives and treat people like individuals, leaving the identity politics to the left. Your choice :)
We restrict voting rights from other groups, such as people under 18, even though some of them are much wiser and careful in who they would vote for than many in the current electorate.
In the case of repealing the 19th, I believe a good case could be made for that action.