On a tangential note, I've never understood why payola was supposed to be a bad thing.

Payola is a feedback loop that rewards cash, not free consumer choice, and is more or less guaranteed to enable consumer-hostile monopolies.

At the very best you'll get a race to the bottom like the one that happened in online advertising.

However, I'm most curious about the consumer-hostility that you envision resulting from payola. What is the harm that consumers will suffer?

Grocery stores accept money from food producers for placement within the store. As far as I can see, this is precisely equivalent to payola. Nobody thinks there's a problem there.

If the airwaves weren't regulated by the FCC, why would payola suddenly stop being a bad thing?

The reason it is bad over public airwaves is because the airwaves are communal property. The spectrum is licensed by the FCC so that all of society can benefit from the limited resource. The FCC therefore sets fair usage rules for the use of those airwaves, and one of the rules is that you can't pay to get airplay.

Assuming you're not in the business of producing music, you can even pay to have your stuff included in public broadcasts as part of the main programming rather than the commercials. This is called "product placement". (If your stuff was music, it would be "payola".)

You have yet to advance any argument that payola is a bad thing; you've limited yourself to "it's against the rules".