The flaw in this question is basing an overall judgment of a person's suitability for office based on their motives. Just because a political candidate has a motive for making speeches of this nature that are loaded with promises and seem amazing, doesn't mean that they will not deliver.
So this argument is an attack based not on facts but against the character/motives of the politicians.
I hope this helps. Please let me know if you have any other questions.
