A few years back, AF chief Norton Schwartz remarked (IIRC) that the AF was "all in" on the F-35. This can mean "fully supportive" but it can mean committed in the pig-and-hen sense. In gambling terms, you've already mortgaged the house and maxed your credit cards. The USAF has no other options that stop an already old fighter force from continuing to age.
If the service wants to have 1800 tactical aircraft in the inventory and wants to work with a nominal lifetime of 30 years it has to buy 60 aircraft a year, but so far has bought 187 F-22s and 103 F-35s in the past 20 years - so it is 910 aircraft, or 15 years' production, in the hole. If it was to stop buying F-35s or fail to reach the 60/year replacement rate, the hole will keep getting bigger.
The question is what must be sacrificed to feed the F-35. The A-10 is at the top of the list, but the abandonment of F-16 modernization has to mean that those aircraft (with primitive EW and 1980s-tech mech-scan radars) have a limited effective life. F-15 upgrades are the next place to look for money: will the EPAWSS EW upgrade get funded?
And before the F-35 production program for the AF is anywhere near half done, the F-22 will be at mid-life.