Leaving aside Carter's foreign policy bungling, many of the factors that resulted in those failures were actually outside of policymakers' control, especially domestic/economic ones. So, he might have done better than Carter, but he would have lost if his performance is not good enough to overcome the tough situation, or is perceived to be not good enough by the electorate.
It's like a guy who scores 40/100 is better than a guy who scores 20/100 but still fails because he does not meet the 50 requirement to pass as the exam is too hard.
In addition, party fatigue is a thing. If Ford won, by 1980, the Republicans would have already been in power for 12 years. Party fatigue could result in a defeat in a fair weather scenario, let alone the late-1970s.
And if he does even worse than Carter, well, that would be a no-brainer scenario. Well, Democratic massive victory, although not at Reagan's scale due to GOP advantage in the South/Southwest.