That is not accurate. The F-35A is not only able to reach the battlefield faster than the A-10C, it also has a greater unrefueled range. It doesn't matter what payload an aircraft carries if it can't get there in time. And the remaining A-10's are aging rapidly; maintenance costs are going to accelerate just to keep them flying at all.

Sure, in a world of unlimited resources the Air Force would be better off with a new dedicated CAS platform. But the reality is that there will never be funding for that, so here we are.