Haha do you think China's government will officially say 'We are / want to be a superpower'?
My conclusion is based on a perception that Chinese leaders of today increasingly feel they have the economic, political and military clout to assert themselves in ways that often put themselves at odds with the US. The responses to US actions in the current manner (e.g. the reaction to the Trump phone call, the bellicose reaction to the US-led effort to induct India into the NSG, etc.) are undertaken in a manner unthinkable 20, maybe even 10 years ago. Many countries who have a bone to pick with the US on various issues (Pakistan on foreign affairs, India on trade / visas) often have to quietly suck it up because the US controls most international bodies, holds the purse strings, has the biggest guns. The recent level of Chinese statements and the tone of such statements seem to signify an aspiration to be a superpower at par with the US. Only the USSR demonstrated such an attitude in modern history.