The questions involved have to do with should we build this tech, not how to build this tech. To argue otherwise means that the vast majority of people should not be allowed to have opinions on the ethics of nuclear weapons, medical procedures, or any other topic where they are not subject matter experts.

AI tech and the ethics of using it is rightly a political topic, since it has the potential to affect everyone on the planet.

Preemptively saying that certain viewpoints have no place at the table simply means the political discussion will move from a friendlier environment within Google to the (likely more hostile to Google's interests) environment of general politics in the U.S. Personally I think that might be a better outcome, but from Google's standpoint it's potentially a disaster since it might result in heavy regulation of their business.