A frequent topic here has been about how expensive it can be to fly out of Fresno. Specifically, how the lack of lower-cost airlines (especially Southwest) has kept prices high. Even though the city was the birthplace of Allegiant Air, that company is now based in Las Vegas and only flies from Fresno to Vegas (although they have previously flown to Honolulu and Mesa/Phoenix as well). Frontier is low cost, but their flights to Denver come and go based on airport incentives. On the nicer end, Jetblue is nowhere to be found, nor is Spirit at the low end.
In comparison, Boise (metro population of 709,845, less than Fresno’s 972,297) has low cost flights to 15 different cities through Southwest, Allegiant, and Frontier. A couple of years ago, I looked at some peer cities and found this: