I still don't see how this works out as an advantage for the little guy. At best, for every ad the new startup buys, the big incumbent buys two and you're back

I still don't see how this works out as an advantage for the little guy. At best, for every ad the new startup buys, the big incumbent buys two and you're back to more or less where you started. Worst case, the big incumbents and shady scammers buy up the majority of the advertising time, training consumers to ignore ads and making it even harder for a legitimate newcomer to get their foot in the door.