Trump was mocking behavior - the being inconsistent part of it - not mocking disability. It's the difference between mocking somebody for their views and state

Trump was mocking behavior - the being inconsistent part of it - not mocking disability. It's the difference between mocking somebody for their views and statements who merely happens to have a disability and mocking somebody for having a disability. The latter is what people thought he did; the former is far less inherently objectionable.