Completely speculation with no evidence here, but we will not see f35's used in anything important. My bet is that both the physical build materials and the electronics are compromised by the Chinese. If we used them against China, we'd get our asses handed to us. Why shoot them down when they could just hack them and turn them into kamikazes against us? This is why there has been so many delays with them. The MIL doesn't want to admit they're compromised.