> The only solution to this problem is public-only funding of campaigns.
I fail to see how that addresses any of the issues we have "earned media" from the cable "news" propaganda (I'm not using that word lightly here) networks or the "Citizen's United" style documentary production which would not likely be curtailed by the change you propose. All you do is shift the money from being thrown at the 16 minutes per hour of advertisement blocks to the 44 minutes per hour where we don't notice we are being advertised to.
At that point you have just placed a limit on spending which is what some other countries do anyway. Personally I think we should move towards banning the use of any paid for media in politics. If candidates want to reach voters they should do it in person or using social media. And voters should be able to ignore some candidates and listen to others based on who they follow. And candidates should need to succeed without the normal public sphere rather than the weaponised media landscape.
The problem is that Candidate X owes her success to donated money. She is now beholden to her donors, not her constituents. Democracy, for sale by the dollar isn't democracy, it's a slide into oligarchy.
The only solution to this problem is public-only funding of campaigns.