They are telling other countries that they must engage in a certain legal structure that has not been accepted universally in the nation they are based.
I would have a problem with them doing it anyway even if it was, but the fact that it is directed to Singapore more than Nebraska makes it not only culturally imperial but culturally hypocritical as well.
Google is not the US, the US is not Google. There's nothing hypocritical about their position just because their headquarters happen to be based on the US. Google's culture is what matters.
And they aren't telling anyone what they must do. They're giving their opinion. Just like you are doing here to them.
I would have a problem with them doing it anyway even if it was, but the fact that it is directed to Singapore more than Nebraska makes it not only culturally imperial but culturally hypocritical as well.