Of all the proposed amendments, this, IMHO, is the most quixotic. You will never get people to vote in favor of taking away their right to vote.
Yet, a great many people are willing to simply give away their vote either to an influx of illegal new citizens through amnesty, or a President who simply feels that the representatives elected by the people are nuisances to be ignored or passed over by Executive Order.
A diligently conducted COS can be the tool to remedy this trend as the founders intended.