As for political manipulation, well, yes, of course it's going on. It should. But that should be a function of the political parties and individuals, not government. Government should be neutral in and of itself. So that entire argument is a red herring that doesn't touch on the policy or it's use.
how can government be neutral if it has goals and is made of people who generally are not neutral.
The government wants to recruit people for the military. That is advertising and advertising is manipulation
The government wants people to pay their taxes. redesigning their forms to expedite that is manipulation. They can't be asked to deliberately engineer their forms in the worst possible way just to avoid any charge of "manipulation", when in fact such effort would be its own form of manipulation to sway people from filling out forms and submitting them (which really does happen).
You cannot exist in the world without manipulating or being manipulated. Gravity manipulates you. Words manipulate you. Etc.
To argue one should not use better manipulation techniques over some artificially enforced sense of nobility is like refusing to use the laws of physics because you think it gives an unfair advantage.