If their opinion is changing only for the worse because they’re being corrupted by their corporate benefactors, like Kamala, that’s worse than someone who doesn’t change their stance. If their stances started out the same, obviously the person who stubbornly stays the same would be preferable.

This isn’t a way Trump and Kamala differ, though, regardless of his statements on the matter, and Kamala started out with a very left-leaning voting record, so this shouldn’t really impact anyone’s choice of candidate.