The article, at least at first, doesn't seem to be concerned with minority rights. It's concerned about institutions necessary to actually maintain a democracy. Things like an independent press, independent judiciary, and election apparatus not unduly influenced by the current party in power. Degrading or getting rid of these things is anti-democratic even if a majority of people want it. A majority of voters can want single-party or even single-person totalitarianism, but that is still anti-democratic. Hitler won elections, too.