It reads pretty self-explanatory to me:

Prescott Municipal Airport director Robin Sobotta, confirmed to ATW’s sister publication Aviation Daily that public pushback against air service with single-engine aircraft led the city to change its stance.

...but the projected subsidy needed to make the service viable was deemed too high, city officials said.

Two other bidders, Advance Air and Mokulele Airlines, faced the same challenges. Advance proposed King Airs, while Mokulele proposed single-engine operations.

Public didn't want single-engine planes and the subsidy price was too high.