I would understand that the Supreme Court did not wish to turn control of elections over to domestic and foreign corporations. But they did.
So in this person’s view, the American is a helpless unthinking automaton, who cannot decide for himself how to vote, but rather must mindlessly cast his vote for whatever candidate has received the highest volume of advertising paid for by the powerful "domestic and foreign corporations."
The voter can only vote based on the sheer number of advertisements to which he is exposed, because he is incapable of actually watching those advertisements in terms of content and making decisions based on the content of the advertisement rather than on the sheer volume of them. The voter is incapable of deciding for himself whether or not the advertisements represent truth, whether or not the ideas presented in them are in his best interest, or whether or not the policies advocated by them are policies he particularly wishes to espouse.
If the voter is exposed to 3000 advertisements for candidate Alpha, and only 2000 advertisements for candidate Bravo, then the content of those 5000 advertisements is irrelevant; the voter must vote for Alpha because he has seen 1000 more advertisements for him than he has seen for Bravo.
This does not apply, of course, to party loyalists who will vote for their party’s candidate regardless of any amount of advertising; will do so even if that candidate is dead. That has happened, in fact; a person won a election in a “safe district” several weeks after he died. To complete the comedy, his wife claimed the right to serve in his place. A party loyalist will vote for a Poodle if it is labeled as a candidate of the party; no advertising required.
If those who believe that the Citizens United decision “turned control of elections over to corporations” are correct, then our democracy is so badly broken that it hardly matters what the Supreme Court decides regarding elections.