Yes, there would be more toilets available to the public, and they would be in better condition too. Fast food restaurants often make you buy something to use the bathroom anyway.
Extraordinary claims require extraordinary evidence.
It's common sense. Why would anyone set up a free public toilet and maintain it? Toilet access is like any other good and most efficiently procured and distributed through the free market. Banning pay toilets did not result in free toilets popping up everywhere in the US. People just use store bathrooms or government-owned bathrooms instead (which are often dirty).
Do you live in NYC? I would think that the piss-smelling subways would be a good argument against pay toilets in themselves.
Public bathrooms are often dirty, especially ones in fast food restaurants. Where do you expect poor people or people without coins on hand to go?