While the F-15C does have more range than the F-35, the F-35 has more payload. The F-15E does have more payload, but that's a twin seat fighter-bomber that lean

While the F-15C does have more range than the F-35, the F-35 has more payload. The F-15E does have more payload, but that's a twin seat fighter-bomber that leans more towards the "bomber" part and isn't directly comparable The A-10 is, frankly, a terrible close air support platform. Its only advantages are lower cost per hour and the fact that by being low and slow it's more visible to grunts on the ground. However, it's slower to respond to CAS requests; more vulnerable to MANPADs which the F-35 can simply fly over and radar-guided SAMs that the F-35 can avoid with stealth; and lacks modern electronics like the F-35's electro-optical sensor suite (aka cameras) making it more likely to cause friendly fire incidents. The gun has been too small to destroy tanks since the T-72, and too big be efficient killing BMPs and trucks, and also requires the plane to come in low and slow in the optimum flight path for getting shot down by MANPADs For the close air support mission, you're either doing it in contested airspace in which the A-10 is too vulnerable compared to the F-35, or in uncontested airspace where a drone can do the dame job just as well if not better for cheaper